Outfit yourself for adventure with these 100% merino wool base layer bottoms from REI Co-op. The breathable, ultrafine wool naturally resists odors and pilling. Flat seams are comfortable on the skin.
Key Features
Best Use
Multisport
Fabric
100% merino wool
Sun-Protective Fabric
Yes
UPF Rating
30
Moisture Wicking
Yes
Quick Drying
Yes
Underwear Weight
Lightweight
Inseam (in.)
25.5, 28 inches
Gender
Women's
Sustainability
Fair Trade Certified™ Factory - From a Climate Label Certified brand
Highlights
Ultrafine 185 g/m² merino wool offers a soft feel without any itchiness
Made with 100% merino wool that naturally breathes, wicks sweat, dries quickly, and resists odors and pilling
UPF 30 sun protection
Flat seams and merrow stitch construction reduce chafing
Soft elastic waistband has a low profile so it's comfortable under other layers
Crotch gusset allows full range of movement
Semifitted to hug the body for optimum performance
Locker loop makes it easy to hang these to dry or just keep them off the ground
Inseam length: 28 in. inseam; Petite sizes: 25.5 in.
Machine wash warm, gentle cycle; use wool wash product; do not twist or wring; remove promptly; do not bleach; tumble dry low; cool iron; dry cleaning not recommended
Made of wool sourced according to third-party animal welfare standards adopted by REI Co-op brand
Made in a Fair Trade Certified™ factory
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
Materials & care
Machine wash warm, gentle cycle; use wool wash product; do not twist or wring; remove promptly; do not bleach; tumble dry low; cool iron; dry cleaning not recommended
Sizing & fit
Semifitted to hug the body for optimum performance. Inseam length: 28 in. inseam; Petite sizes: 25.5 in.
How to use
### How to Choose Base Layers
**Which material is best?**
- **Wool:** highly moisture-wicking and odor-resistant
- **Synthetic:** durable and less expensive
- **Silk:** soft and lightweight for casual activities
**Match the temp to the trek**
- **Lightweight layers:** best for moderate to cool temperatures
- **Midweight layers**: best for cold temperatures
- **Heavyweight layers:** best for below-freezing temperatures
**Find your fit**
- Must be close to skin to efficiently wick sweat; should fit comfortably snug
- Base layer is for moisture control; your mid layer is for warmth
## Better gear is built together
From feedback to field testing, all of our gear is dialed-in by REI Co-op members. Their adventures informed every stitch and detail—making for better, longer-lasting gear.
Made of wool sourced according to third-party animal welfare standards adopted by REI Co-op brand. Made in a Fair Trade Certified™ factory. 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.
