Design and Details Made in the USA Cushioned Performance fit Slip, bunch, and blister resistant Arch support alleviates foot fatigue and bunching for long-running comfort with zero slippage Heel tabs offer extra protection behind the heel from friction and keep debris at bay Merino Wool is a great athletic fiber that actively moves moisture, fights foot funk, and feels silky smooth Lightweight socks breathe well, feel great, and regulate temperature during tough workouts 53% Nylon, 44% Merino Wool, 3% Spandex Lycra