The Ultimate Bison Sock is our coziest, plushiest, and warmest sock ever, boasting nearly 800 5-star reviews. Crafted with our signature BisonShield™ fiber, it features salvaged bison wool intercepted from the waste stream, making it soft on you and the planet. Reinforced heel and toe, along with ribbed arch support, ensure durability and comfort. Features: - Reinforced heel and toe - Ribbed arch support - 62% wool, 22% nylon, 15% bison wool, 1% spandex - Small fits W 6-10, M 5-8 - Large fits W 10-13, M 8-12 - Made in the USA - Recommended: use a Guppyfriend Washing Bag to avoid microplastic shedding