The fine inner sock is made from Meryl that draws moisture away from the foot and transfers it to the outer sock. The dri-release outer layer is great at drying to leave you feet feeling dry and comfortable. This double-layer construction prevents friction from occurring on your feet and blisters from appearing. The durable heel and toe sections help you put the miles in making Twin Skin a trusted partner of many runners. The LYCRA SPORT fibre ensures a close, comfortable fit.