How to Choose Base Layers
REI Co-op Lightweight Half-Zip Base Layer Top - Women's
$29.93Compared to $44.95*Save 33%
A synthetic base layer for moderate temps, the women's REI Co-op Lightweight Half-Zip keeps you dry and comfortable whether you're venturing into the mountains or trekking across open desert.
- Recycled polyester/spandex wicks sweat and dries quickly
- Fabric has a soft and silky feel for next-to-skin comfort
- UPF 50+ sun protection
- High neck coverage with a half-zip front for ventilation when you're working hard
- Underarm gussets ensure you can reach and move with ease
- Shaped shirttail hem stays tucked when you stretch
- Locker loop for hang-drying
- Weight (size S): 5.7 oz.
- Machine-wash warm; wash separately; do not use bleach or fabric softeners; tumble dry low and remove promptly
- REI Co-op brand is certified to The Climate Label; we actively fund efforts to reduce carbon emissions across our business and support climate projects around the world
- Contains materials that meet the bluesign® criteria
- Made in a Fair Trade Certifiedâ„¢ factory
Imported.
View all REI Co-op Women's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | Partial-zip |
| Fabric | 94% recycled polyester/6% spandex (bluesign approved) |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50+ |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Lightweight |
| Sleeve Length | Long Sleeve |
| Gender | Women's |
| Sustainability | Contains materials that meet the bluesign® criteria Contains recycled materials Fair Trade Certified™ Factory From a Climate Label Certified brand |
REI Co-op Clothing - Women's
| XXS | XS | S | M | L | XL | 1X | 2X | 3X | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18W | 20W | 22W | 24W | 26W | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Numerical Size | 00 | 0-2 | 4-6 | 8-10 | 12-14 | 16 | 18 | 20-22 | 24-26 | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 |
| Bust | 31 | 32-33 | 34-35 | 36-37 | 38.5-40 | 41-42.5 | 43-45 | 47-49 | 51-53 | 32 | 33 | 34 | 35 | 36 | 37 | 38.5 | 40 | 42.5 | 45 | 47 | 49 | 51 | 53 |
| Sleeve Length | 29.5 | 30 | 30.5 | 31 | 31.5 | 32 | 32.5 | 33.5 | 34.5 | 30 | 30 | 30.5 | 30.5 | 31 | 31 | 31.5 | 31.5 | 32 | 32.5 | 33.5 | 33.5 | 34.5 | 34.5 |
| Waist | 24.5 | 25.5-26.5 | 27.5-28.5 | 29.5-30.5 | 32-33.5 | 34.5-36.5 | 37.5-39.5 | 40.5-42.5 | 44.5-46.5 | 25.5 | 26.5 | 27.5 | 28.5 | 29.5 | 30.5 | 32 | 33.5 | 36 | 38.5 | 40.5 | 42.5 | 44.5 | 46.5 |
| Hip | 34 | 35-36 | 37-38 | 39-40 | 41.5-43 | 44-46 | 47-49 | 50-52 | 54-56 | 35 | 36 | 37 | 38 | 39 | 40 | 41.5 | 43 | 45.5 | 48 | 50 | 52 | 54 | 56 |
| Inseam | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 |
Sizing Notes
Measurements are stated in inches unless otherwise indicated. Size chart values represent body measurements, not garment measurements. Some women's pants are available in petite and tall sizes. Typically petite sizes fit women 4'11" to 5'3". Regular sizes fit women 5'4" to 5'8". Tall sizes fit women 5'9" to 5'11".
PETITE: Generally, as compared to regular sizes, petite sizes are 2.5 inches shorter in inseam, 1 inch shorter in body length, 1.25 inches shorter in sleeve length and ¾ inch shorter in total rise.
TALL: tall sizes are 3 inches longer in inseam, 2 inches longer in body length, 2.5 inches longer in sleeve length and 1.25 inches longer in total rise.
Capri or cropped pants have an intentionally shorter inseam—reference the technical specs instead of this chart.
Inseam is measured to the floor.
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Location:Brooklyn, NY
Height:5'2"
Age:25–34
Weight:100–125 lbs.
2 weeks ago
Comfortable, great in fall weather
Yes , I recommend this product
Pros: Great temperature regulation, lightweight, fabric feels great on skin, fast drying. Cons: Gets smelly quickly like most synthetics, really wish it had thumb holes! Wore this as one of two main base layers on a shoulder season trip and it was great but I hate how easily synthetics get smelly. It was easy to rinse out every day and would dry in an hour or so hanging on the back of my pack while moving. As a standalone layer it was great while moving in fall temps. Size chart would put me at a small but I hate skin tight or compression feeling from base layers, so a medium was perfect for me, still close to the skin but not bothersome.
Height:5'2"
Age:25–34
Weight:100–125 lbs.
Location:Texas
Age:55–64
Weight:125–150 lbs.
Height:5'1"
7 months ago
Best base layer I have found!
Yes , I recommend this product
My favorite base layer ever!! Ended up buying two! These are great for hiking, camping, and running. Keeps you warm in cold weather and the fit is comfortable but not clingy.
Age:55–64
Weight:125–150 lbs.
Height:5'1"
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