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The Baselayer That Actually Works Harder Than You Do
Right, so here's the rather splendid bit: this isn't your standard thermal top. It's a seamless, recycled merino baselayer engineered with infrared technology that genuinely helps your body perform better, recover faster, and stay at precisely the right temperature. Whether you're training, recovering, or simply attempting to look fabulous whilst being functional, this does the heavy lifting so you don't have to.
Why Choose Our Merino Baselayer?
Infrared Performance Technology: The fabric boosts nitric oxide production in your muscles, making them more elastic and priming them for better performance. You'll notice improved endurance, strength, flexibility and mobility while feeling considerably less muscle soreness afterwards.
Strategic Cooling Zones: Expandable side and arm panels with targeted cooling beneath the arms and across the shoulders mean you stay comfortably regulated whatever your activity. The technology warms and cools as needed, storing thermal energy 63 percent longer than standard fabrics.
Recovery Acceleration: Whether you're bouncing back from exercise, an injury or surgery, the infrared technology genuinely accelerates the process. Users report a 25 percent average reduction in pain and an 80 percent average reduction in soft tissue injuries through muscle priming.
Breathable and Quick Drying: The fabric dries 65 percent quicker than average baselayers, so you're not left feeling damp and rather sorry for yourself.
Seamless Construction: No seams means no chafing, no irritation, and considerably more comfort during extended wear.
Sun Protection: SPF35 plus rating provides meaningful UV defence, because we're thoughtful like that.
Naturally Antimicrobial: Merino wool handles odour brilliantly, so this top stays fresher longer between washes.
Product Details
Fabric Composition: 50 percent recycled KYnergy infrared polyester and 50 percent sustainably sourced merino wool
Design: Fully seamless 3D knit with expandable side and arm panels for personalised fit
Sizing: Available in XS through XXL. The model pictured (183cm tall) wears a Large. Our garments don't require a skin-tight fit for the infrared technology to work, so size according to your preference or go up one size if you prefer looser styling.
Care: Hand wash only. Do not tumble dry. As this is a recycled, undyed ecoknit product, you may notice natural colour variation and character within the weave, which we rather like.
Optimal Use: Wear for at least 30 minutes before exercise, throughout your workout, and for at least one hour afterwards to maximise performance and recovery benefits.
What You're Actually Getting: A properly handsome baselayer that looks after your body as much as you look after it. The technology is subtle, the comfort is rather obvious, and the results speak for themselves.
This is the kind of piece that quietly transforms how you feel during and after activity. Rather good value for something engineered this thoughtfully.
SHIPPING + RETURNS
THE RATHER IMPORTANT BITS
This rather lovely piece ships directly from our brand partner - we work with independent brands who are absolutely brilliant and work frightfully hard to create beautiful things.
SHIPPING DESTINATIONS
Now, here's the thing - our wonderful brand partners ship to lots of different places, but not all of them can ship worldwide.
Some are brilliant at international shipping, others prefer to keep things closer to home.
At checkout, you'll see exactly where this particular brand can send your goodies.
We're terribly sorry, but shipping costs do vary rather wildly depending on where you are in the world. The exact figures pop up at checkout - no nasty surprises!
RETURNS
You have 14 days to return items.
Now, we absolutely adore our brand partners - they work incredibly hard and we do try to support them as much as we possibly can. So I'm rather afraid we have to pass the return postage costs back to you. Frightfully sorry about that!
🌍 PLEASE CHOOSE THOUGHTFULLY:
Our wonderful partners put their hearts into everything they make.
Ordering multiple sizes to try at home is rather hard on our planet and makes things jolly difficult for these brilliant independent creators.
When in doubt, do ask us first!
PAYMENT
We're frightfully modern and accept all the usual suspects:
Visa, Mastercard, American Express, PayPal, Apple Pay, Google Pay, and Shop Pay
SECURE AS HOUSES
Everything's properly encrypted and secure - your details are safer than the Crown Jewels!
All prices in lovely British pounds £ GBP, though international chaps will see converted prices.
Any payment pickle? We're here to help sort things out! Contact us
We Have Lots More Like This.........
Hello, we are Sostter....
Sostter began, as all good ideas do, with a lively conversation and a shared sense of frustration. Why had the world of independent design become so serious, so samey, so… beige? Where was the spark, the imagination, the sheer joy of discovering something that made you stop and stare?
We dreamt of a marketplace that celebrated difference — where curious minds could explore a world of independent brands, design-led makers, and thoughtful artisans. A space that felt exciting, human, and beautifully imperfect.
Today, Sostter brings together remarkable people and their creations — from London to Lausanne, Brooklyn to Berlin — uniting makers and discoverers through craftsmanship, creativity, and conscience. Every object tells a story, and every purchase supports an independent brand doing things differently.
This is just the beginning. But enough about us — step inside, explore our world, and see what catches your imagination.
Giving Back
We’re proud to support Sutton Night Watch, a grassroots UK charity making a real difference in the lives of those facing homelessness. Through regular donations of stock, supplies, and essentials, we back their mission to offer warmth, dignity, and practical help to anyone in need — right where it matters most.
Sell with us
Sostter partners with independent brands that intrigue, inspire, and bring something genuinely different to the world of fashion, design, and living.Join us!