Classic Thermal Merino Base Layer 1/4 Zip – Women's

Cold-weather trail runs, winter hikes, and frigid camp mornings — this is our go-to heavyweight merino base layer for women who don't slow down when temps drop. 100% merino wool in an interlock knit regulates body heat and kills odor naturally, no matter how hard you're working. The quarter-zip lets you shed heat fast without stopping to strip layers.

• 100% merino wool interlock knit delivers real warmth, moisture management, and natural odor resistance through long days and high output
• Quarter-zip collar gives you fast, on-the-fly ventilation when the climb heats up — no need to stop and dig through layers
• Raglan sleeve construction keeps fabric out of your way during high-output movement; flatlock seams reduce chafe against skin
• Slim fit with back-seam-to-front wrap follows body contours without bunching under a shell or pack harness
• Available in standard sizes XS–XL and plus sizes 1X–4X across a wide range of solids, heathers, and prints