250 GSM is our everyday cold-weather standard — warm enough for winter city days, breathable enough for the trail.
Fabric weight guide
Which merino weight is right for you?
GSM is grams per square metre — how much fabric there is, not a warmth rating. Every weight is the same soft 17.5-micron Australian merino: it wicks sweat before it turns cold, insulates when it is cold and ventilates when it is warm. Lighter fabric breathes and dries faster; heavier fabric holds more heat when you stop moving. Choose by season and by how hard you will be working.
Warm & hot weather · 60°F+ / 15°C+ — and high effort in any season
Best for: summer hiking, running, cycling, hot-climate travel, everyday tees and office wear; the next-to-skin layer under a 250 when you work hard in winter
Pick this if: you want a shirt that stays fresh for days, dries in an hour and keeps you cooler than cotton in the heat — or you simply run hot
Think twice if: you will mostly be standing still in the cold; on its own a lightweight layer has little insulation to offer
Cool to mild · 40–65°F / 5–18°C
Best for: spring and fall as a standalone top, summer evenings, cool-morning hikes and commutes; winter as a base under a mid-layer
Pick this if: you want one merino layer that covers most of the year, or you are unsure between light and mid — this is where most people should start
Think twice if: you run cold and your winter is genuinely cold: go straight to 250
Cold · 20–45°F / −7–7°C — the classic winter base layer
Best for: skiing and snowboarding, winter hiking, cold-weather work, frosty fall mornings; top-and-bottom sets so your legs are not the weak link
Pick this if: you run cold in fall, want the classic winter base layer, or spend active days below freezing under a shell
Think twice if: you overheat easily on hard uphill efforts — a 165 or 190 underneath, 250 over it, is the better system
Deep cold · below 25°F / −4°C — especially when you stop moving
Best for: ice fishing, hunting stands, camp at altitude, winter mornings spent waiting rather than walking, a house that never quite gets warm
Pick this if: warmth matters more than breathability, you are chronically cold, or your winter involves long spells standing still outdoors
Think twice if: you will be working hard — it is too warm for a sweaty climb, which is exactly the point
A base layer works by sitting close to the skin, where it can move moisture — loose is not more comfortable, just slower. Between sizes? Size down for a next-to-skin layer under a shell, size up to wear it on its own or over another layer. Merino stretches with wear and springs back after a wash. Heavier weight is not itchier: itch comes from coarse fibre, and every weight here is the same superfine merino.
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Description
Manga Larga de Lana Merina para Mujer
Experimenta la suavidad de la fibra más fina de la naturaleza. Nuestra manga larga de lana merina para mujer está confeccionada con lana merina prémium, ultrafina, lujosamente suave, increíblemente ligera y diseñada para ofrecer comodidad durante todo el día.
La termorregulación natural mantiene tu cuerpo perfectamente equilibrado: cálido en climas fríos y fresco cuando hace calor. Absorbe y libera la humedad sin esfuerzo, eliminando el sudor y previniendo los olores. Con elasticidad natural, protección UV y un tejido transpirable, esta manga larga es tu prenda ideal para la comodidad, el rendimiento y la elegancia atemporal.
Care
Washing and Drying Instructions
- Turn Inside Out
- Machine Wash Cold: Gentle cycle with like colors
- Detergent: Mild or wool-specific
- Lay flat to dry
- Storage: Wash before storage and keep in a dry place, using airtight containers or vacuum-sealed bag to prevent moth.
- Do NOT Use: Fabric softener or bleach!
Our Guarantee
- 30 Day Satisfaction Guarantee
- 1 Year Warranty
THE FABRIC
WHY MERINO WOOL
01INSULATES WHEN WET
Wool has the remarkable ability to absorb up to 30% of its weight in moisture without ever feeling wet or sticky. In the event that it does become wet, wool outperforms cotton and polyester materials by providing superior insulation.
02ANTI-MICROBIAL
Merino Wool fibers possess a natural ability to repel bacteria in moisture or sweat, effectively wicking it away. This means you can wear our products without worrying about foot fungus or unpleasant odors.
03FIRE RESISTANT
Merino Wool offers excellent insulation against high temperatures and has a natural resistance to catching fire. In the rare event of ignition, it self-extinguishes without melting and adhering to the skin, unlike synthetic fabrics.
THE FABRIC
01MOISTURE WICKING
Merino Wool regulates moisture levels on your skin by absorbing any perspiration or sweat from your body, allowing it to evaporate from the fabric into the surrounding atmosphere.
02UV PROTECTION
Leave your sunburn worries behind as you ascend to sunlit peaks. Our lightweight layers provide a UPF rating of 25, while the midweight and expedition options offer an even higher UPF rating of 50+
03RENEWABLE
Merino Wool boasts a minimal environmental footprint and seamlessly reintegrates into the natural world. Shear a merino sheep in the morning, and by afternoon, they're happily grazing their way towards renewing next season's wool clip
Questions people ask about merino
What is merino wool, and what makes it different from regular wool?
Merino wool comes from Merino sheep and is measured in microns — the thickness of a single fibre. Merino.tech uses 17.5 micron Australian merino, which is roughly a third the thickness of the coarse wool most people remember from old jumpers. Finer fibres bend against the skin instead of pressing into it, which is why merino feels soft rather than scratchy while still insulating, breathing and resisting odour naturally.
Is merino wool itchy?
No. Itch is caused by fibre diameter, not by wool itself. Fibres above roughly 22 microns are stiff enough to trigger the prickle response; ours measure 17.5 microns, well under that threshold. Every piece here is 100% Australian merino with no synthetic blend in the body fabric, so there is nothing rough sitting against your skin.
How do I wash merino wool without ruining it?
Turn the garment inside out, machine wash cold on a gentle cycle with like colours, and use a mild or wool-specific detergent. Lay it flat to dry. Never use fabric softener or bleach — softener coats the fibre and destroys the breathability you paid for. Merino resists odour, so you can wear it several times between washes, which is the easiest way to make it last.
Is merino wool warm enough for real winter?
Warmth is set by fabric weight, measured in grams per square metre. 165 and 180 are lightweight layers for runs and mild days. 200 is the everyday weight. 250 covers autumn through proper cold and is the most popular choice for skiing and hiking. 320 is heavyweight, made for standing still in real winter — ice fishing, chairlifts, cold work outdoors.
Does merino wool shrink?
It can, but only under heat and agitation. Hot water and a tumble dryer cause the scales on the fibre to lock together permanently. Cold water, a gentle cycle and flat drying prevent it entirely. Follow that and the garment keeps its shape for years.
