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  • Polartec Power Wool fabric combines natural and synthetic fibers in a bicomponent fabric that ensures the technical advantages of each are achieved
  • Top is extremely comfortable to wear and has excellent moisture management due to the combination of wool on the inside and synthetic on the outside
  • Flatlock seams offer extra elasticity and prevent abrasion
  • UPF 35 sun protection
  • Modern design lines ensure multiuse on and off the mountain
  • Athletic fit


View all Mammut Women's Long Underwear Tops

REI membership


Best Use Snowsports
Shirt Style Crew
Fabric 66% polyester/34% wool
Sun-Protective Fabric Yes
UPF Rating 35
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Lightweight
Sleeve Length Long Sleeve
Gender Women's

Size chart

Rated 5 out of 5 by from Fantastic Long Underwear Shirt Let me start off saying I'm 6'0" with fairly broad shoulders for a girl and 115lbs, so finding anything with long sleeves that fits properly is a struggle. The sleeves are perfectly long enough to fit me, and the shoulders are broad enough for me. I have a lot of issues with fabric texture (especially wool because I'm Autistic), but I have to say I haven't had any issues with this material being itchy or uncomfortable. The material is extremely light, so I hardly feel like I'm wearing anything, but it still keeps me plenty warm. Even if it's not completely skin-tight, it still works amazingly. I highly recommend if you're looking for a good midweight set of long underwear, this shirt and the pants that go with it are a fantastic choice!
Date published: 2017-06-09
Rated 5 out of 5 by from Perfect base layer for all sorts of weather I bought this as a light layer to wear hiking and climbing: best decision I have ever made when it came to picking out a long sleeve. I'm very particular about fabric when it comes to things on my arms and this did not disappoint. I actually went back and bought it in all the colours I loved. Hiking wise, it's amazing. Layers easily, super soft, fitted in a non-constricting, yet flattering way, breathable. It keeps you warm in windy conditions as a single layer if it's around 70 degrees or so. Yet, it's not overly warm if it's not windy and the temperature is pushing 75 degrees or so. That being said, I do tend to run on the colder side. For climbing, it's also perfect. The fit still allows for easy movements and flexibility. Keeps you warm on the rock but breathes so when you start to work up a sweat, you aren't dying. If you do work up a sweat while wearing it or after washing, it dries very quickly. The other benefit is that it is super small when folded so it doesn't take up any room in your pack.
Date published: 2017-01-11
Rated 5 out of 5 by from Soft and warm This is great for hiking, layering, or anytime. The sleeves are nice and long, and the fabric is so soft. This will be perfect for my upcoming backpacking trip as the base layer under fleece.
Date published: 2017-06-01
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