The Lorpen T3 Heavy Trekker Over Calf Socks features Lorpen s unique T3 construction with maximum cushioning for protection and warmth The combination of Merino Wool and PrimaLoft reg Yarn results in faster drying and wicking than just Merino Wool while still maintaining a comfortable feel against the skin Best suited for cold or damp weather hikes where moisture is an issue Primaloft reg Yarn is made up of ultra-fine polyester fibres which are finer than cashmere resulting in a luxuriously soft feel while providing unparalleled moisture wicking When hiking climbing or doing any aerobic activity your body works up a sweat and emits heat and perspiration but when you suddenly sit idle you can easily start to freeze with an insulation that absorbs water Primaloft reg fibres wick moisture away from the skin and trap body heat This is a fantastic sock for hikers looking who need warmth padding and dryness