REI Co-op Midweight Base Layer Bottoms - Men's

REI Co-op Lightweight Base Layer Long-Sleeve Crew Top - Men's

REI Co-op Midweight Long-Sleeve Base Layer Top - Men's

Soft, moisture-wicking 100% merino wool makes the men's REI Co-op merino midweight base layer bottoms an ideal next-to-skin layer for high-performance

Merino Midweight Base Layer Bottoms - Men's

REI Co-op Midweight Base Layer Bottoms - Men's

REI Co-op Lightweight Base Layer Tights - Women's

REI Co-op Midweight Base Layer Tights - Women's

The men's REI Co-op lightweight base layer bottoms wick and breathe to keep you comfortable from the first cold steps of morning to sweaty

Lightweight Base Layer Bottoms - Men's Tall Sizes

REI Co-op Merino Midweight Base Layer Bottoms - Men's

Best Base Layers of 2024 – iRunFar

REI Co-op Midweight Base Layer Crew Top - Women's

REI, Underwear & Socks, New Rei Coop Midweight Base Layer Bottoms Mens

Icebreaker 260 Merino Tech Thermal Leggings with Fly - Men's

The kids' REI Co-op Midweight base layer bottoms are warm and very good at wicking moisture, making them an ideal base layer for highly aerobic

Midweight Base Layer Bottoms - Kids

REI Co-op Midweight Base Layer Bottoms - Men's

Men's Base Layer Bottoms & Thermal Underwear