Travelsox Flight Travel Socks OTC Patented Graduated Compression, TS1000 75% Coolmax/15% Lycra/10% Nylon Imported FITTING GUIDE- (SMALL W 5-8 M 5-7) (MEDIUM W 8.5-11 M 7.5-10) (LARGE W 11+ M 10.5-13) (XL M 13.5+) Travelsox Fibers Stretch more than regular socks, for tighter fit select next size down. COOLMAX FIBER- Ideal Compression (10-18 mm Hg) Machine Wash Inside out. ORIGINAL TRAVEL SOCKS- Designed in Italy using a patented design that helps stimulate blood flow, reducing swelling, and can prevent DVT. COMPRESSION- Real Graduated Compression starting mid foot for arch/plantar support and prevent pooling of blood, Two hand adjust to sit right below the knee. TECHNOLOGY- Helps Tired Aching Legs, Prevents Edema, Spider Vein and Varicose Vein Support, reduces swelling, blisters, and Cramps, 100% Made in Italy.