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- Helly HansenHH Durawool Crew Long-Sleeve Shirt - Women's$59.73Save 33%compared to $90.00(2)2 reviews with an average rating of 2.5 out of 5 starsUnderwear Weight:LightweightSize Type:RegularREI OUTLET
- EnduraBaabaa Blend Long-Sleeve Base Layer Top - Women'sNew arrival$64.97Save 27%compared to $90.00(0)0 reviewsUnderwear Weight:MidweightSize Type:RegularREI OUTLET
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Related Expert Advice articles
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
Whether you're working out, hitting the trail, or just enjoying a relaxing day, the perfect underwear is critical. We've rounded up our favorites!
Learn which clothes to bring backpacking in order to keep your pack light while making sure you'll have everything you need.
Fabrics
- Synthetic: moisture-wicking, quick drying, durable, but can hold on to odor
- Wool: moisture-wicking, odor-resistant, cooling in warm weather, can be less durable
Styles
- Bikini: less rear coverage, thinner waistband, higher-cut leg
- Briefs (women's): full-cut briefs offer more coverage in front and back; hipsters offer medium front coverage and back with higher rise
Briefs (men's): close fit and good support, but less thigh coverage
- Boxer brief or boy shorts: snug fit, good coverage, longer cut extends down to the upper thigh
- Boxers: looser fit, added coverage can prevent chafing but prone to bunching
- Thongs: lightweight and quick-drying but provide the least coverage
- Sports bras: compression and support during high-output activities like hiking and running
Our gear reviewer and REI Co-op Member tester evaluated this four-person camp shelter in windy Wyoming. Here's how it performed.
Read full article: Gear Review: Testing the REI Co-op Westward 4 Tent
Learn the basics of layering clothing so you can stay comfortable outdoors. Find out how to use base layers, middle layers and outer layers to stay comfortable and active.









