An all-season favorite, the Classic All-Season Merino Base Layer Long Sleeve can be sported as a base layer in the fall or summer when it's time to go backpacking. This base layer features Core Spun technology—which features Merino wrapped around a nylon core for added durability while still keeping the comfort of ultra-soft, responsibly sourced Merino next to skin. Our Raglan sleeves eliminate shoulder seams for perfect comfort under a pack, and smooth merrow stitching wraps from side to front to keep you looking as good as you feel.