Arc’teryx Cerium LT Review: Complete List [2023 Guide]

We tested it and would like to share our Arc’teryx Cerium LT review and compare it with its most popular contenters. The following chart that we have prepared will give you an insight about the entire post, if you need a short answer:

Down Jackets #Arc’teryx Cerium LTPatagonia Down Sweater HoodyNano Puff Insulated
Score82/10078/10074/100
Price TagCheck it on AmazonCheck it on AmazonCheck it on Amazon
Our Selection ForSuper LightweightBest for Town UseThe Most Popular
Warmth90/10090/10060/100
Water Resistance70/10060/10080/100
Fit80/10070/10060/100
Compressibility100/10070/10080/100
Features70/100100/10090/100
Weight11.0 ounces15.1 ounces11.9 ounces
Fill Type850 Fill Goose Down800-fill Advanced
Global Traceable Down
60 gr Primaloft Gold Eco
Expert ReviewCerium LT vs SLDown Sweater Hoody ReviewNano Puff Review
Credits for specs: Arc’teryx and Patagonia

Related Article: Patagonia vs Arc’teryx Complete Package

Long Story Short: Our Review Arc’teryx Cerium LT Hoody Review

We would like to share the highlights from our Arc’teryx Cerium LT Review. First of all, I purchased Arc’teryx Cerium LT Hoody; therefore I am going to share my experience mostly on this product. Also, I will give the technical information related to Cerium versions LT vs SL vs SV for your consideration. In this review, I will present the other customer reviews and the most frequent questions that are answered by users and manufactures. Let’s take a look!

Cerium LT Review
Arc’teryx Cerium LT Review Overview

This is a truly amazing product that hits the sweet spot in terms of temperature range. I have used it almost every day since it arrived, finding it to be quite warm and comfortable down to almost -10C. At that point I usually wear a heavier parka anyway. I have also worn it on days that go up to 5C or higher. it covers this range of temperature incredibly well for something that’s so…LIGHT! It is very light, packs down into a handy bag and has good pockets. The Nocturne colour is a beautiful blue that is great if you’re tired of black but don’t want something too bright.

Cerium LT Review - Hoody - Rhapsody Packed
Arc’teryx Cerium LT Review – Hoody – Rhapsody Packed

My only complaint and it’s a big one…. it’s too darn warm! I run hot and this jacket is extremely good at trapping heat. Granted, it breathes well as a standalone but if I wear this under a shell, as a mid-layer you, better believe I sweat like mad. I guess that’s not really a complaint but rather a testament to just how amazing and warm this super lite puppy really is.

It is much warmer than the Atom LT. I can wear with a base layer down to about 4 degrees Celsius. I have worn the Arc’teryx Cerium LT below freezing with no complaints to being cold.

It’s been shoved into my pack for days on end and pulled out in extreme conditions as a mid-layer, used as a primary layer when shoveling snow, back country skinning on a powder day, used for wind protection against a cool breeze, etc. It’s handled everything I’ve thrown at it, like a champ, and although I take care not to abuse it, I’ve never really babied it and I got to say it looks as good today as it did almost three years ago, with substation use!

I’m usually a large and the large fit well, but pretty snug. Still have full range of motion. But go a size up if you are buying for urban use. Material is very lightweight but I have not had an issue with abrasion or tearing even when hiking with a backpack and brushing against rocks.

One cons comes to my mind! The zipper is small and flimsy but it’s always worked for me. I haven’t had issues with the zippers yet, but how thin they are concerns me and I suspect they would be a failure point. Speaking of the zipper, in the upper 10 cm there is some fabric covering it to feel more comfortable. This fabric leads to the zipper to get stuck a little when pulled up. It’s not a big deal, but could be solved better I guess.

I would happily recommend this jacket (and do) to everyone. Thanks Arcteryx for another thoughtfully produced piece of technical gear!

Breathability Review of Arc’teryx Cerium LT Hoody vs Squamish vs ATOM LT

The Aeretica fabric on the Cerium will be slightly more breathable than the fabric on the Atom LT and the Squamish as it is a thinner and lighter weight fabric. The Cerium LT is much warmer than the Atom LT. I can wear with a base layer down to about 4 degrees Celsius. I have worn the Arc’teryx Cerium LT below freezing with no complaints to being cold.

Cerium SL vs LT Review: Key Differences

COMPARISON OF CERIUM LT VS CERIUM SL: We compared Cerium SL vs LT from price, pros & cons, warm weight, water resistance and compressibility stand points of view. Here is the short summary of key differences between Cerium LT and SL.

From price stand point Cerium LT is more expensive than Cerium SL, the overall score we gave them are almost the same. It is 75 for Cerium LT and 78 for Cerium SL.

  • Cerium LT is warmer and heavier than Cerium SL.
  • Their weights are as follows: 340 g – 12 oz for LT and 238 g – 8.4 oz for SL.
  • Both of them are not very water-proof, so make sure you know that before doing a final decision.
  • Compressibility of SL is better than LT, the most important reason is the weight of each product.
  • The insulation – down fill of the each product are the same. Both Cerium LT and SL are using 850-fill goose down.
  • Baffle construction is Sewn-through for both of them.
  • The main fabric used in Cerium LT is Arato 10 Nylon, whereas Arato 7 Nylon for SL.
  • Usually both of them include stuff back and the compression method is to zips into its own pocket with clip-in loop.
  • Pockets: Both of them have 2 zippered hand pockets.
Comparison of Cerium SL vs LTSLLT
Warmth7090
Water Resistance8070
Fit10070
Compressibility100100
Features7070
Here is the full review of Cerium SL vs LT
Abbreviations of Arc’teryx Products Cerium SL vs LTAntonymModification on the Arc’teryx Products
SLSUPERLIGHTSuperlight materials and design, emphasizing light weight and packability over durablity.
LTLIGHTWEIGHTHigh performance, minimalist design that is durable for its weight.

Cerium LT shows better durability compared to Cerium SL, usually durable fabrics are heavier and thicker. However, Cerium SL is the best option for a super light layer for a trip.

Thorium AR vs Cerium LT Review: Key Differences

We compared Thorium AR vs Cerium LT from price, pros & cons, warm weight, water resistance and compressibility stand points of view. Here is the short summary of key differences between Thorium AR and Cerium LT.

Abbreviations of Arc’teryx Products Thorium AR vs Cerium LTAntonymModification on the Arc’teryx Products
ARALL ROUNDHigh performance weather protection and materials, emphasizing versatility for multiple activities.
LTLIGHTWEIGHTHigh performance, minimalist design that is durable for its weight.

From price stand point Cerium LT is more expensive than Thorium AR.

Cerium LT and Thorium AR have almost the same temperature ratings. Indeed Cerium has 850 Fill Down with 340-12 oz weight, whereas Thoriun has 750 Fill Down with 490 gr-1lb and 1.3 oz. This means that the reduction of the fill down is compensated by the weight increase in thorium.

Comparison of Thorium AR vs Cerium LTThorium ARCerium LT
Warmth10090
Compressibility60100
Features9070
Durability7060
Weater Resistance4070
Here is the full review of Thorium AR vs Cerium LT

Both of them are not very water-proof, so make sure you know that before doing a final decision. Also, it is really hard to dry them out back.

Compressibility of Cerium LT and Thorium AR are almost the same, they have a compression method that zips into its own pocket with clip-in loop. They arrives with an stuff sack.

Baffle construction is Sewn-through for both of them.

Arc’teryx Product Line Thorium AR vs Cerium LTWhat is it for?
THORIUMVersatile down insulated mid layers that provide durable warmth. Light by construction.
CERIUMStreamlined, minimalist and lightweight technical down insulation. High warmth to weight ratio.

The main fabric used in Cerium LT is Arato 10 Nylon, whereas Thorium AR is Arata 30 Nylon. This is the key difference between them, Thorium AR is more abrasive resistant than Cerium LT.

Pockets: Both of them have 2 zippered hand pockets. In addition to this Thorium AR has an internal zippered pocket.

You can find hoodless options in the market for both of them.

Arc’teryx Atom AR vs Cerium LT Review: Key Differences

We compared Atom AR vs Cerium LT from price, pros & cons, warm weight, water resistance and compressibility stand points of view. Here is the short summary of key differences between Atom AR and Cerium LT.

From price stand point Cerium LT is more expensive than Atom AR.

Cerium LT and Atom AR have almost the same temperature ratings. Indeed Cerium has 850 Fill Down with 340-12 oz weight, whereas Atom has 80 g/m2 underarms, 60 g/m2 hood.

Atom AR is an insulated jacket and DWR coated which repels the water, therefore it has a better water resistance compared to Cerium LT.

Atom AR is not very compressible and it is a heavier jacket than Cerium LT. AR is 12 oz, whereas LT is 16 oz.

Built in material is different than each other, Cerium’s material is Arato 10 nylon, however, Atom’s material is Gossamera nylon.

Pockets: Both of them have 2 zippered hand pockets. In addition to this ATOM AR has an internal zippered chest pocket.

Down Sweater vs Arc’teryx Cerium Lt Review: Key Differences

We compared Down Sweater vs Cerium LT from price, pros & cons, warm weight, water resistance and compressibility stand points of view. Here is the short summary of key differences between Down Sweater and Cerium LT.

Although their performances are very close to each other, the tag price of Cerium LT is much more than Patagonia Down Sweater. Cerium LT and Down Sweater have almost the same temperature ratings. Indeed Cerium has 850 Fill Down with 340-12 oz weight, whereas Down Sweater has 800-fill Advanced Global Traceable Down- 448 g | 15.8 oz. Down Sweater is heavier and less compressible compared to Cerium LT.

We can conclude that both of them are not water-proof, so make sure to have a shell whenever you plan a trip to wet environment. Built in material is different than each other, Cerium’s material is Arato 10 nylon, however, Down Sweater’s material is DWR finished Recycled polyester ripstop, it is more durable compared to Cerium LT. Both of them have sewn-through baffles. Pockets: Both of them have 2 zippered hand pockets. In addition to this Down Sweater has an internal zippered chest pocket. Hoodless option for both of them is available in the market place.

For the detailed comparison, we recommend reading our Arc’teryx Cerium LT vs Patagonia Down Sweater post.

Arc’teryx Cerium LT Hoody vs Atom AR?

The Cerium LT will be a bit warmer than the Atom AR if worn as a layering piece because down is better at thermal regulation and at storing body heat than synthetic insulation. Whether the Cerium LT will be warm enough for you in -15 degrees Celsius, I cannot say. Regarding temperature ratings of insulated garments-whether garments or another brand’s-those are general ratings that are most accurate under ideal conditions. Ideal conditions are those when your core body temperature is not affected by hunger, fatigue, dehydration and lack of circulation.Also, whether a jacket is warm enough for an individual depends on one’s own core body temperature (some people get hot easily and some people tend to get cold easier); it depends on what the individual is doing and to what extent (high output vs. low output activities); and it depends on an individual’s own preferences.

Personally, the Cerium LT Hoody would not be enough for me in -15, but then again, it depends on what exactly I will be doing while wearing it.

If you’re comparing the two and want something slightly warmer, then I would recommend the Cerium LT over the Atom AR.

Some Customer Insights for Arc’teryx Cerium LT Hoody

  • From one of my previous Skiing jacket, the Theta AR, I was already familiar with the Stormhood which is, from my point of view, one of the nicest feature of this jacket. The hood naturally snuggles nicely around your head when you put it on which helps retain warmth. You can also use the drawstring and depending on how tight you crank it down, the hood either grips the top of your head, or let it move freely without impairing your visibility. So far, this jacket has mainly been used for backcountry and resort skiing on the East coast which is just about perfect for what I do. It’s extremely warm, lightweight and has all the features you’d want for a down jacket.
  • I love Arc’teryx, have a lot of their gear, and will be buying more in the future. I also love my Cerium LT and it has been my preferred mid-layer this winter (usually too warm out to wear my Cerium SV). However, the dainty zipper on this jacket is very easy to mess up when unzipping. Unless I’m very careful and slowly ease the zipper down to the end as I unzip, the zipper mechanism will come off its track. I understand that Arc’teryx was going for lightweight, but this particular compromise isn’t worth it. For a small amount of additional weight, a more robust zipper like on the Cerium SV would be welcomed.
  • One thing you don’t always appreciate about Arc’teryx until you own a few different pieces is how you can just buy one size. I bought my Cerium and my Theta in the same size, and they are cut differently so that it just works out. One goes on top of the other, they fit well together and don’t impair movement. Most other brands will require that you size up to get the shell to layer, or size down to get a svelte mid. I hope it is a positive statement that one of the best parts of the Cerium LT isn’t specific to the jacket, but specific to the brand.

Arc’teryx Cerium LT Review – Pros & Cons

Pros/Cons based on the survey are as follows:

Pros (+): 

  • warm, 
  • color looks great, 
  • lightweight, 
  • packable
  • snug fit
  • comfortable
  • sizing is accurate, 
  • well-made -surprisingly durable,  does not inhibit range of motion while climbing,  stuff sack actually fits the jacket
  • indispensable
  • style
  • fit
  • warmer than advertised,
  • durable face fabric,
  • high loft
  • breathable
  • packable 850-fill down (stuff sack included),
  • adjustable down insulated storm hood,
  • interior chest pocket
  • nice athletic fit
  • good mobility
  • compressible

Cons (-): 

  • zippers possibly won’t last
  • the down doesn’t distribute evenly
  • down (feathers) may escape but this is normal
  • sleeves a bit too short (xl)
  • no breast pocket zipper need to be more robust.
  • zippers are small can be hard to grip
  • fit is not great for shorter more muscular/people,  shorter thicker people have to go up in size
  • no waist adjustment

The Purpose of Usage of Arc’teryx Cerium LT Review – based on 211 Customer Reviews:

  • Glamping, city life looking cool
  • Skiing snowshoeing
  • Daily living /hiking in the Yukon
  • Trekking / Mountaineering / Expedition
  • Hiking
  • All Round
  • Casual wear, miltary wear
  • Backcountry Camping, Backpacking, Cold WX Hiking,
  • Ice climbing, mountaineering
  • Sking, Snowshoeing, hunting
  • Hiking. All around usage.
  • traveling, camping
  • Daily using.
  • Jeeping
  • Basecamp, Belay jacket
  • snowshoeing, winter camping.
  • skitouring, mountaineeri
  • Commuting
  • walking my dog
  • trekking at high altitude; motorcycles
  • Variety of backcountry activities
  • Backpacking.
  • Rock climbing,
  • bike commuting,
  • Outdoor wear.
  • You name it
  • Hunting
  • Film technician.
  • montagne
  • Senderismo.
  • Suburban living
  • Commuting in NYC
  • Going to work
  • Search and Rescue, Static winter activities
  • Nordic skating
  • XC Skiing
  • Alpin ski
  • Utah winters

Technical Details From Arc’teryx Cerium LT Review

Materials of Cerium LT

  • Coreloft™ 100 (100 g/m² ) insulation. Made with highly crimped multi-denier siliconized polyester yarn, this lightweight, breathable, and thermally efficient, 100% polyester staple fiber is very compressible and has excellent loft retention.
  • 850 fill European grey goose down
  • Coreloft™ 40 (40 g/m²) insulation. Made with highly crimped multi-denier siliconized polyester yarn, this lightweight, breathable, and thermally efficient, 100% polyester staple fibre is very compressible and has excellent loft retention.
  • Arato ™ 7 – 100% nylon

Care of Cerium LT

  • Machine wash in warm water (30°C).
  • Do not use fabric softener.
  • Front load washing machine recommended (use a mesh bag for top loading machines).
  • Tumble dry on low heat with tennis balls.
  • Do not iron.

Technical Features of Cerium LT

  • Moisture-resistant outer face fabric
  • Insulated
  • Great warmth-to-weight ratio
  • Lightweight
  • Compressible and packable
  • Wind resistant

Construction of Cerium LT

  • Down Composite Mapping strategically places synthetic insulation in areas where moisture may buildup and down in areas for maximum warmth
  • Super lightweight Arato™ 7 face fabric with DWR finish repels moisture

Design & Fit of Cerium LT

  • Trim fit keeps warmth close to the body

Hood Configuration of Cerium LT

Cerium LT Hood Configuration Review
  • Adjustable hood drawcords
  • Down insulated StormHood™
  • Low profile hood

Collar Configuration of Cerium LT

  • Soft, smooth lined collar

Zippers & Fly Configuration of Cerium LT

  • Full front zip with chin guard
  • Corded zipper-pulls reduce noise and are easy to grab
  • Minimized zippers help reduce weight and bulk

Cuff & Sleeves Configuration of Cerium LT

  • Elastic cuffs

Hem Configuration of Cerium LT

Arc'teryx Cerium LT Hem Adjuster Configuration
  • Straight hem
  • Adjustable hem cord seals out drafts

Pocket Configuration of Cerium LT

Arc'teryx Cerium LT Hand Pockets
  • Two hand pockets with zippers

Integrated Features

  • Includes stuff sack

Fabric Treatment

  • DWR (Durable Water Repellent) finish repels moisture

Sizes:

The size options for the Arc’teryx Cerium LT: S, M, L, XL and XXL

Weight:

 215 g / 7.6 oz

Arc’teryx Cerium LT Hoody SIZING

BODY MEASUREMENTS IN INCHES – Here is the full Size Chart for Arc’teryx Cerium LT:

SizeSleeveChestWaistHip
XXS313428331/2
XS323630351/2
S333832371/2
M344034391/2
L354337421/2
XL364640451/2
XXL375044491/2

ARC’TERYX SL VS LT VS AR

We thought that it would be better to provide the list of the Arc’teryx Abbrevations, since we mentioned the modifcations such as SL vs LT vs AR. Here is the brief summary of Arc’teryx SL vs LT vs AR abbrevations and the corresponding product modifications:

Abbreviations of Arc’teryx Products SL vs LT vs ARAntonymModification on the Arc’teryx Products
SLSUPERLIGHTSuperlight materials and design, emphasizing light weight and packability over durablity.
LTLIGHTWEIGHTHigh performance, minimalist design that is durable for its weight.
ARALL ROUNDHigh performance weather protection and materials, emphasizing versatility for multiple activities.

Arc’teryx Cerium LT Hoody Men’s

CERIUM

Streamlined, minimalist and lightweight technical down insulation. High warmth to weight ratio.

LIGHTWEIGHT

High performance, minimalist design that is durable for its weight.

ESSENTIALS

Versatile high performance designs for diverse activities and conditions.

DOWN INSULATION

Highly efficient natural insulation that compacts well and offers excellent warmth to weight.

$450.00

CERIUM SV HOODY MEN’S

SEVERE WEATHER

Most durable materials and weather protection, for prolonged exposure to severe conditions.

This product has a No Slip Zip™. The main zipper is equipped with “speed bumps” near the collar to avoid self-opening.

CERIUM SL HOODY MEN’S

SUPERLIGHT

Superlight materials and design, emphasizing light weight and packability over durablity.

Bottom LIne for Arc’teryx Cerium LT Review

For me it’s the best goose down jacket I ever owned. It’s a goose down yes, but it’s a class of its own. Because it’s combination of weight to warmth is excellent – plus you don’t look like a goose yourself wearing it. What most other goose down jackets with significant less isolation grade do. I love the hoody. It makes you feel warm around the neck and head, so I feel much warmer in a chilly wind, without looking weird. When not using the hoody it keeps the neck warm when the zipper is all the way up.

I’ve come to the conclusion that this is the best lightweight down jacket I’ve ever owned. I think I like the best about this jacket is that it packs down so small and I can pull it out whenever the temperature drops so easily. It regains its loft very quickly.

Thanks you for reading our Arc’teryx Cerium LT Review!

If you are looking for a sturdy winter jacket you can check out our Arc’teryx Thorsen Parka Review.

Please get in contact with us for any question or any advice to improve this post.

Arc’teryx Cerium LT Hoody: Q&A

I just brought Arcteryx Cerium LT, I also have a Rab Microlight Alpine which has Nikwax coating on outside,does the Cerium have something similar?

The Cerium LT has a delicate face fabric so our team chose not to add any water repellent product to it. Another reason is that down doesn’t perform well under wet condition. We would always suggest to wear it under a shell especially in a humid environment.

What are the compressed dimensions/ volume? can you tell me just how small this packs please? Ideally the dimensions so I can calculate the volume myself or please just tell me the volume when compressed in its stuff sack.

Our stuff sack dimensions are as follows:

STUFF SACK HEIGHT

XS: 23.0cm

S: 23.0cm

M: 23.0cm

L: 26.0cm

XL: 26.0cm

XXL: 26.0cm

STUFF SACK WIDTH

XS: 33.6cm

S: 34.8cm

M: 36.0cm

L: 37.2cm

XL: 38.4cm

XXL: 39.6cm

Since this is a “trim fit” does that mean it will not layer well on top of other layers? How would a med in the Cerium fit over a Med Gamma MX?Or should I go with the Thorium?

The Cerium is certainly fitted to fit lighter to the body than the Thorium. It will be ideal over a light base layer as it is meant as a mid layer item to go underneath an outer layer.Although the Thorium will be a better fit over layers, it is usually best to put a water and wind resistant item like the Gamma MX over top of down mid layers like the Cerium or Thorium as these items will not resist wind as well and when wet, they lose their heat retaining properties.

How long is the warranty of this product?

warranty covers defects in materials or workmanship are covered for the practical lifetime of the product. Material refers to zippers, buckles and fabrics. Workmanship refers to seams, seam tape and construction. Damage due to wear and tears such as rips, tears, abrasion or UV degradation, misuse or neglect is not covered under our warranty policy but may be repairable for a fee.

What is the best down jacket for taking long walks around town in winter?

The Cerium LT or Thorium AR are probably the best options for your temperature range and activities.The Cerium SV will likely be too warm. The Cerium is a trimmer fitting model and is slightly less durable when compared side by side to the Thorium AR. I would suggest the Thorium AR for everyday use as a stand alone piece.Running in either jacket is going to be too hot, and once you start to sweat, the down could become damp which would have a negative impact on the loft of the jacket.

Is the storm hood on the Cerium hoodie LT designed to be helmet compatible?

The Cerium LT Hoody is not helmet compatible. It is an adjustable low-profile hood and may fit over certain helmets, like a low profile climbing helmet, but it is not designed to fit various sized helmets.                                      

What color is Nocturne?

The Nocturne is a dark blue.

Will my jacket “loft up” after shipping?

The down should loft back up after shipping, especially after wearing it a couple times or after hanging it for a few days. You can throw it in the dryer on low/no heat with a couple of tennis balls as well. This should do the trick.

Looking at getting a Cerium LT from last year at a retailer. Looks like the waist has no cinch cord vs this year’s version. Will this affect the warmth effectiveness and/or performance?          

There will be no difference in warmth and performance. Because you will not be able to cinch the bottom, wind may travel up the jacket more easily in extreme conditions. That being said, this jacket is designed to be worn primarily as a mid-layer so your shell will block out all wind.

has the cerium LT a waterproff shell?

The Cerium LT is not waterproof unfortunately.

Arato 10 vs  Airetica (Nuclei) nylon is it at least as tear/abrasion resistant as Airetica used in the Nuclei? or worse?

Airetica, the face fabric used for the old Nuclei, is slightly more abrasion resistant than the Arato 10 currently used for the Cerium LT Hoody.

Comfort zone of Cerium       I know its highly variable, but can you give a rough idea of what temperature the Cerium can be worn at comfortably as a stand alone jacket with minimal activity.Is it similar in warmth to the Thorium?

The Cerium LT will be almost identical in warmth to the Thorium AR. The cerium is more of a mid layer piece but like the Thorium, it can be used as both a mid and outer layer item.We do not give temperature ratings as your other layers, the temperature that your body is already at, and the humidity will all play key roles in the warmth of this piece. This however, along with the Thorium AR is our warmest mid layer item. In a zero wind and zero humidity environment, the Cerium will even be warmer than the our Kappa Hoody which has 140 g/m² of Coreloft insulation.

Total fill weight – men’s size Large       How many grams of 850 down & how many grams of Coreloft are in a men’s size Large – 2019 version?

In the large, the amount of down is approximately 336.4g for the 2019 model. The amount of Coreloft insulation will be 80 grams per square metre in the Gussets, Cuff and Front Hood, 100 grams per square metre in the Yoke.

Hood fit and layering       Is the hood designed to fit under or over a climbing or skiing helmet?   

The hood is not designed to be worn over or under a helmet, though it may fit over a climbing helmet. For some people, layering the Cerium LT Hoody underneath the Nuclei AR (both the same size) will work.

How does the Shimizu colour compared to Rigel or Deep Cove?

Shimizu will be an incredibly light blue, in contrast to Rigel which is a very true blue or Deep Cove which has a green hue.

How bad is it to keep this jacket in its compression sack for long periods?       I’m on the road right now and I will be for 4 or 5 more months. I have this jacket with me, and I have it stuffed into the sack that it came with. I will need it eventually in my journey, but not for another 7 or 8 weeks. Should I be taking it out of the sack every once in a while and allowing the down to loft even though I won’t be wearing it?

I want to store this gear as decompressed as possible as often as possible – just like any jacket made with high quality lofting insulation (Primal-/Coreloft and down).I own lots of down and Primaloft One (and some Coreloft) products and I never store/keep them in a compressed state longer than absolutely necessary. I dare say I near love my pieces and want to have them around and delivering top-tier functionality for as long as possible (which can be a long time).

One way of shortening such products’ otherwise long life spans is to store them compressed for long periods of time and not otherwise look after them (such as regular cleaning and over-sweating in them)Decompress your jacket in the evenings and avoid storing it highly compressed in your luggage if you have room to do so. Just because it can be highly compressed, doesn’t mean it has to be stored in such a compact state. 

Do you know exactly how much (fill weight) 850 fill power down there is for size Medium?

There is 102g of down in the size Medium.

What color is Neptune ?

It is a silver grey colour with a touch of blue-green.

Does the back length change with sizing?

The center back length does change slightly with sizing.The length for the Cerium LT Hoody in a size medium is 28.3 inches. A small is 27.3, large is 29.3, and x-large is 30.4 inches.                                     

Which standard (EU or US) do the CUIN ratings for your down jackets refer to?

Fill-power is a universal measurement. We do not have any other standards or ratings for our down products.

Wind Resistant       How wind resistant is this jacket? Just wondering if I would be comfortable using it as a standalone jacket on the hill on days warmer than -10C. I plan to use it as a base layer to my pro shell, but just curious how wind resistant without a pro shell overtop it would be?

The Cerium LT Hoody is ideal as a midlayer but can certainly be worn as a standalone piece. Mid to strong winds may push through the Nylon and Down layers but lighter strength winds are usually blocked.

How would Cerium function as a belay type jacket over top of Gamma MX? Would it layer well?

The Cerium LT is a trimmer fitting item that will function ideally as a mid layer. You could certainly use it as a belay jacket for warmth over a Gamma MX, however please keep in mind that this item is ultra lightweight and uses a thin face fabric. It should also not be used in rainy conditions as an outer layer.Ideally, this item should be used underneath a Gamma MX or another type of outer shell.For a great warm belay Jacket, the Solo or Dually Belay Hoodies are great items that are more abrasion resistant and designed for this specific purpose.

Warranty       Does this item come with a life-time warranty like other items usually do?

At Arc’teryx, the warranty for all of our items, including the Cerium LT, is the lifetime of the product. This means that if the product fails because of manufacturing or material defects, the item is covered. If the damage however is wear and tear or the item has reached the end of its expected use, this is usually not covered.