The Hiking HD Sock is a High Density protective padded sock. Using dense padding, as opposed to thick padding, it protects feet without adversely affecting the fit of the shoes. The Hiking HD Socks were designed for use in cold to mild conditions, keeping feet dry, comfortable and odor free all day long. Features: - Thermal insulation - Anti-bunching instep - Flat toe seam - Size mark detail - Arch band - Secure top - Leg band - Higher heel increases durability and heel protection - Drymax interior fabric - Moisture attracting outside layer - Discontinued Model/Color Sizing: - Small: Women's shoe size (5 - 7), men's shoe size (3.5 - 5.5) - Medium: Women's shoe size (7.5 - 9.5), men's shoe size (6 - 8) - Large: Women's shoe size (10 - 12), men's shoe size (8.5 - 10.5) - X-Large: Men's shoe size (11 - 13)