Sweat is what makes you cold
You warm up on the climb, you sweat, you stop, and the wet shirt against your skin pulls the heat out of you. The fix starts with what touches you.
Defender 2026 · How to layerLayer 1 decides
Layer 1 decides
if you’re cold
Most people blame their jacket when they get cold. Usually it is the shirt underneath, holding sweat against their skin. Here is how the base layer works, and the one we wore under everything in the Yukon.
Shop the bamboo long sleeveBamboo blend · Made in Ukraine
So the base layer has one job
Keep sweat moving away from your skin. The bamboo-blend knit helps move moisture away and breathes, so you stay drier and the layers above stay warm.
And it has to be comfortable for twelve hours
Soft against your skin, seamless at the shoulders where pack straps sit, with a little stretch so it moves when you do.
Then the fleece goes on top
Power Grid when you are moving, Polartec 200 when you stop. Every Defender layer is built to sit over a good base layer.
The Yukon kit
Build the rest of the system
Layer 1 · BaseЛонгслів Bamboo ActiveSoft bamboo. Keeps sweat off your skin.₴2,540Shop it
Layer 2 · MidPolartec PowerGrid Ultralight - Quarter-ZipPower Grid. Warm while you move.₴4,770Shop it
Layer 3 · WarmthPolartec 200 Midweight - Ninja HoodiePolartec 200. Hood zips up into a balaclava.₴5,580Shop it
Where this came from
From a sticker to a full layering system
Saint Javelin started in 2022 as a sticker. Four years later we make the whole system, from the shirt next to your skin to the fleece you sleep in, in Ukraine.
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February 2022It started with a sticker
Journalist Christian Borys prints a sticker: a saint in green robes holding a Javelin. He hopes to raise a few hundred dollars for Ukraine. Days later Russia launches its full-scale invasion, and the saint goes around the world.
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2022Made in Ukraine
We stop being a meme and start being a maker. Production moves into Ukraine, and we start learning how to make things that last.
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November 2023The first Defender
Our first cold-weather collection: a fleece, and the padded work socks people still buy from us today.
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2024Polartec arrives
Defender moves to Polartec: quarter-zip fleeces, a sherpa hoodie and thermals. Customers start calling them the best fleece they own.
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2025Into the mountains
The Karpathian Sherpa fleece, shot with Ukrainian veterans hiking the Carpathian mountains. Our first real step into outdoor gear.
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2026Tested in the Yukon
Defender 2026: Polartec Power Grid, Micro 100, 200 and High Loft, cut and sewn in Ukraine. Before it went on sale we wore it for five days and 55 km off-trail in the Yukon backcountry, with nights down to −10 °C.
Bamboo Active Long-Sleeve
Get the bamboo long sleeve
Лонгслів Bamboo Active
₴2,540
66% bamboo, 28% cotton, 6% spandex. Made in Ukraine.
- Feel good against your skin all day: a soft bamboo blend (66% bamboo rayon, 28% cotton, 6% spandex).
- Stay comfortable as you heat up: the knit helps move sweat away from your skin and breathes.
- Move freely under a pack: seamless shoulders and just enough stretch.
- Wear it everywhere: under fleece on the trail, on its own at the gym, at work, on the plane.
- Made in Ukraine.
5★ reviews
What people say about our bamboo long sleeves
★★★★★
“effectively wicks sweat away from your body and dries quickly, I wear one of these almost every day at work. … excels as a stand alone layer or as a base layer in the winter.”
Hunter
★★★★★
“Ideal as a base layer in colder weather or as an outer layer in warmer weather. … The fit is excellent, not too baggy and not too tight in all the right places.”
Ben
★★★★★
“True to fit, breath well and very comfortable.”
Leslie Bashow
★★★★★
“I work a very physical job mostly in varying environmental conditions and I value this shirt.”
Number Six
★★★★★
“Very comfortable and light. Nice cut and fabric, feels like it’ll last”
Dundee
★★★★★
“This shirt is quality material, the bamboo is soft and washes like new.”
CaliforniaMom72
Store-wide: 4.89★ from 5,469 reviews (Judge.me, 28 October 2026).
Questions we get
What is it made of?
66% bamboo rayon, 28% cotton and 6% spandex. The spandex gives it stretch, so we do not call it plastic-free. It is mostly plant-derived fibre instead of the polyester most base layers are made of.
Is it a hiking base layer or an everyday shirt?
Both. We wore it under the Defender fleece in the Yukon, and it is just as good on its own at the gym or at work.
How does it fit?
A standard, close fit that layers cleanly under a fleece. Size guide on the product page.
Where is it made?
In Ukraine.
