Combining the luxurious quality, wicking, and naturally odourless qualities of merino wool with the superb insulation of PrimaLoft® yarns, the Castelli Alpha 18 Socks are ideal for your coldest adventures and when going out on the bike feels like a necessity more than anything else. Nylon heels and toes introduce durability and arch support bands hold the socks in place.Features:PrimaLoft®/merino wool blendArch support bandNylon heel and toe18cm ankle height