Scent Shield expedition weight socks are constructed with innovative "V" heels for better fit, flat seams to reduce blisters. The Expedition is 12", has polypropylene for added warmth and is available in M/L and XL/2XL. Scent Shield Expedition Sock w/ S3T: S3T antimicrobial technology to aid in odor control 4 Direction Stretch comfort 50% Silver, 15% Italian Wool, 15% Acrylic, 15% Polyamide, 5% Lycra Constructed of a multiple density knit in order to provide three important elements: - Optimum cushioning - Moisture control - Comprehensive fit Extra flat seams to eliminate bothersome ridges that can hurt your toes Italian wool inner layer provides a natural warmth and softness when in contact with the skin Lycra is used throughout the sock in order to conserve it's characteristics: keep socks from falling down, no wrinkles, no abrasions, no blisters Polyamide outer layer provides long lasting strength and protection to the sock Shock Blocker in heel and toe area Length. Over the Calf Sizes: Large: 9-12, X-Large: 13-15 Colors: Charcoal