
Description
Warmth-without-overheating in a deliriously soft overshirt. The exterior is a two-ply cotton Italian flannel woven by Albini. The 17.5 micron merino Futurelining on the inside provides a superfine version of nature’s finest performance fabric. The lightweight and extremely breathable Alpha 60 insulation pulls it all together with a gentle high quality warm glow.
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Fabric

Fabric Story
An extremely breathable lightweight insulation system with a soft cotton exterior and beautiful merino interior. Albini Acottonflannel on the outside, super breathable Alpha 60 insulation in the middle and a soft and dry nylon-core merino on the inside.
Alpha is a non-migrating insulation originally designed for US special forces and optimized for breathability and wet conditions performance. It can be paired with a much more breathable face and lining fabrics than almost any other common insulation, which in turn allows us to create much more comfortable cool weather clothing. The nylon-core merino interior keeps things soft and dry with all of the natural performance of merino. On the outside is Acottonflannel, a 100% cotton 190gsm plaid flannel woven and spun in Italy by the masters at Albini, because no one quite does shirting like they do. Like most [alpha]core set-ups this combination traps a nice amount of warmth but begins to dump heat before things get too hot.
Fiber Content
- Acottonflannel: 100% Cotton
- Polartec Alpha 60: 100% Polyester
- Nyloncore Merino: 89% Merino, 11% Nylon
Fabric Weight
420GSM
Fabric Origin
- Woven in Italy
- Knit in USA
- Knit in Thailand
Fabric Water Resistance
None
Breathability
High
Durability
Experimental

Fit
Fidelity
- True to size
- Designed for layering, can be sized down for a closer fit
Shrinkage
Expect slight shrinkage when first washed and dried
Size Chart
in Inches | Measured Flat


Form
Made in
Manhattan
Product Weight
800G(size M)
Hardware
- Cobra Zero snaps, made in Italy
- Cobra low profile snaps, made in Italy
Pockets
- Two merino lined hand pockets
- One external chest pocket on the wearer’s left
Construction Details
- Snap close placket with finger garages
- Two point snap close cuffs
- Hang loop
- Black Lightning 30mm woven label on right hand pocket
Style Number
O637
Revision History
- January 2023:
- Initial release
- Name: Experiment 355 - Acottonflannel Warmshirt
- Colors: Blueorange, Pinkred
- October 2025:
- Name changed: Acottonflannel Warmshirt
- Fit updated: Chest and bottom hem refit
- Colors: Deepshade, Blueshade, Flowerlit


Care
Washing
Machine wash warm
Drying
Tumble dry low

Photography Credits
Photos by Jon-Paul Rodriguez