Bridgedale Base Layer Thermal Liner Boot Sock (Twin Pack) GreyThe Bridgedale Base Layer Thermal Liner Boot Socks are made with an Endurofil rich blend that rapidly transports moisture away from the skin to maintain a dry, warm environment inside the boot. With an ultra lightweight performance fit, they are designed to be worn beneath a primary boot sock to provide continuous warmth and protection multiday hiking, trekking, fishing or general cold weather activities. Key Features Endurofil Construction: Utilises