Sockwell Women's Elevation Firm Graduated Compression Socks 31% Merino Wool, 31% Bamboo Rayon, 30% Stretch Nylon, 8% Spandex Made in US Firm(20-30mmHg) Graduated Compression-Recommended for: All day and every day wear, helpful for those who are, Flying and Traveling, Prolonged sitting or standing, Exercise and recovery Minimizes or eliminates swelling of the feet. Reduces Foot Fatigue Promotes circulation, minimizes swelling, and helps reduce fatigue- Perfect for Nurses, Pregnant Mommies, Sports, Running. Improve your performance and stamina with the best fitting compression sock on the market Accu-fit technology consisting of spandex throughout the sock ensures same fit at the end of the day as when it was first pulled on Light cushion sole provides comfort and a great fit. Size Small/Medium fits US shoe size 4  7.5, Size Medium/Large fits US shoe size 8 - 11 Offers 4 zones of graduated compression, arch support, and Non-abrasive Seamless Toe closure with reinforced Toe and Heel Box helps keep the sock in place throughout the day