Tailored for an anatomical women-specific fit, Guide Thermal OTCs are spun from a savvy blend of fibers, starting with premium merino wool—for deft moisture management and anti-microbial performance—and finished with nylon, polyester, and LYCRA® stretch. High-loft over the calf engineering increases coverage, maximizing warmth where it matters, while Right Angle® arch support improves overall ride across variable trail and river conditions. Made in the USA.