These specially-designed, comfortable compression socks have aluminized threads to reflect your body heat to help enhance circulation, ease pain and reduce swelling. Great for men and women, the thin and lightweight socks have an open-toe design and a non-pinching side zipper for easy on-and-off, plus a comfortable elastic, non-slip band at the top. Machine washable. Nylon and elastane. Choose Unisex: S/M (Fits up to 16" calf) or L/XL (Fits up to 19" calf).