Lorpen Work Antibacterial Coolmax Fresh Socks 75% Coolmax fresh fx/ 15% Nylon/ 10% Lycra Imported Coolmax Fresh fx is the same fiber as Coolmax but has a "spun in" antimicrobial silver additive. The additive keeps the socks smelling clean and fresh longer. Double reinforced toe and heel. High Lycra content keeps the socks wrinkle free and in place Machine wash and dry.