How to Choose Base Layers

Made for cold weather, this Icebreaker base layer top has soft fabric to keep you comfy when you're on the move. Offset shoulder seams and flatlock stitching help reduce friction.




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Imported.
View all Icebreaker Women's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | Full-zip |
| Fabric | Main body: 60% TENCEL lyocell/40% merino wool; inner collar/pocket lining/side panels: 100% merino wool (exclusive of decoration and elastic) |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Heavyweight |
| Sleeve Length | Long Sleeve |
| Thumbholes | Yes |
| Gender | Women's |
| 2X | 3X | XS | S | M | L | XL | |
|---|---|---|---|---|---|---|---|
| Numerical Size | 0-2 | 4-6 | 8-10 | 12-14 | 16-18 | ||
| Bust | 42 - 46 | 46 - 49.5 | 30 - 32.25 | 32.5 - 34.5 | 34.5 - 37 | 37 - 39.5 | 39.5 - 42 |
| Waist | 36 - 40 | 40 - 44 | 24 - 26 | 26 - 28 | 28 - 30.5 | 30.5 - 33 | 33 - 36 |
| Hip | 45 - 48.5 | 48.5 - 52 | 33 - 35.5 | 35.5 - 38 | 38 - 40 | 40 - 42.5 | 42.5 - 45 |
Measurements are stated in inches unless otherwise indicated.
CHOOSING THE RIGHT SIZE: If your body measurements are midway between two sizes, select the smaller size for a tighter fit or the larger size for a looser fit. If your body measurements result in different sizes, we recommend using your chest measurement for tops and your hip measurement for pants.
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[This review was collected as part of a promotion.] icebreaker US gave me this free product to try. I think my real review on this product is a 4.5, but there’s no option for that and a 4 seemed unfair, so it gets a 5 star from me. I used this product on many walks where it ranged from low 40s to 50s. Not freezing, but enough to where i needed something warm. I also took it on 2 falls hikes and 1 short backpacking trip. I think this is going to be my new fleece for backpacking! I’ve always looked for something lightweight but warm, and this is just that. The one small thing i didn’t like about the jacket was the length of it + the tight waist, which is why i wanted to dock it half a star, but that is only a personal preference. The top of the jacket is also slightly see through, but that also helps with the breathability of the jacket. And a couple of the favorite features in this jacket are the thumb holes, as well as the thick neck which is at a great length. And i love the zippered pockets!! Overall i’m really excited about this piece of gear!!
[This review was collected as part of a promotion.] This jacket/shirt is lightweight and well made. It was lighter weight than I thought it would be, but it does add a nice layer of warmth without being bulky like a fleece. I am curvy and was concerned about the fit around my bottom, but the shirt has a lot of stretch. The side panels and along arms are stretchy. Sleeves are plenty long to be able to use the thumb holes comfortably. I have used this piece for outdoor actives, remodeling a house and airplane travel trips. I really like it for airplane travel as it is light, not bulky and does not get stinky. I have washed the piece 4x so far and it has held up well. I have a size medium and that is my typical size in shirts/jackets. icebreaker US gave me this free product to try.
[This review was collected as part of a promotion.] I wore the Women's Merino Blend 300 RealFleece Descender LS Jacket through every kind of adventure this season- backpacking in Olympic National Park's misty forests, paddle boarding across glacial-fed water, and chasing golden larches in the alpine. It kept me warm without overheating, soft against my skin even after long days under a pack, and somehow never smelled like "day three in the backcountry." When cold wind hit across the lake, or frost coated the trail, the RealFleece blend trapped just enough heat while staying breathable and light. It's the one layer I rarely took off from rain-soaked mornings to sunlit ridges- quietly doing it's job so I could focus on the adventure. Icebreaker US gave me this free product to try.
[This review was collected as part of a promotion.] I’ve used this full zip mid layer twice now. The first time was an unexpectedly wet and cold hike at Crystal Mountain and it was amazing. I stayed warm, loved that I could pull the sleeves down over my hands and keep them there with the thumb holes (I have raynauds so my hands get cold very easily). We went for nachos after and I was dry so quickly! The second time was last weekend hiking and camping in BC. This time, I was sweating quite a bit and again it performed by wicking away the moisture and keeping me comfortable throughout. Functionally it’s a beast, but it’s also so cute and after 10 steep miles and a lot of sweating, I wasn’t even stinky! Ha Very impressed!
[This review was collected as part of a promotion.] I live at 10,000 feet, so layers really matter to me and the Icebreaker Merino RealFleece™ Zip Jacket has become one of my favorites. I’ve used it for fishing, hiking, and camping, and it’s been perfect for all of it. The comfort is incredible, is soft, warm, and cozy without feeling bulky. The breathability really stands out too; it keeps me warm when it’s cold but doesn’t overheat when I start moving around. The temperature control feels very natural, like it adjusts with me whether I’m on a chilly morning hike or sitting by the lake fishing. Another big plus is the odor resistance, even after long days outdoors, it still smells fresh. And last but not least, the fit is just right: flattering, comfortable, and easy to layer under a shell or over a base layer. Overall, it’s one of those pieces that just works hard without trying too hard; reliable, comfortable, and made for real mountain living. I’m super happy!
[This review was collected as part of a promotion.] The real test for this jacket was backpacking in shoulder season. Days were warm, but evening in camp the wind picked up and temps dropped. The jacket is warm and fuzzy on the inside but not wind blocking at all. It traps warmth in with the inner ridges. It layered nicely under my puffy and was perfect. Once in my tent the puffy layer was my pillow so I slept in this jacket. It handled my hot flashes and cool downs nicely. After 3 days in it, it had zero smell, and went back on after getting to the car and changing my under layers. I’m usually a L in shirts and this was the perfect fit. (5’6” and 164 Lbs) I have larger muscular arms and shoulders(thanks swimming) and a small ish chest(B cup) It fits nicely without being clingy. The inner fuzz is comfortable against my skin and not at all itchy like some Marino products can be, including on the cuffs and at the neck where they have close skin on fabric contact. It is softer and more cozy after its first 3 washes. Also, as a gram counting backpacker, after a few washes it weighs 319g or 11.3oz.
[This review was collected as part of a promotion.] I have so far worn this jacket as a mid layer for a few colder weather climbing days and it’s been great! It feels just as lightweight as a shirt or sun hoody but keeps me pretty warm while I’m off the wall and comfortable while I’m moving as well. I look forward to using it as a base layer for skiing this winter. Icebreaker sent me this product to test out.
[This review was collected as part of a promotion.] The RealFleece zip jacket has come along with me on quite a few adventures in the past two months and I am pleased with the quality and comfort. The wool material sets this apart from other fleece jackets, and even after strenuous hiking, it has stayed warm and odor free. The cut is comfortable for me and I have gotten many compliments on the style. The jacket is thin and breathable enough to wear comfortably under a raincoat during wet activities. I haven’t found the jacket to be too itchy, to the contrary the fleecy ribbing on the inside is extremely soft, but if you are allergic to wool this would likely still be an issue. The zippers, pockets, and seams feel well made and have gotten smoother after a few wears, and the laundering process (which I have not needed often) was easy with cold water and line drying. Note: icebreaker US gave me this free product to try.
[This review was collected as part of a promotion.]