When it's hot, the fibres of the Merino Wool will absorb your foot's moisture vapours and evaporate them outside of the fabric - keeping you nice and cool so that you don't bake in the heat. On the contrary when it's cold, these moisture vapours will condense inside the fibre, giving off heat and keeping you nice and warm.Get the Men's Trek Sock 2 Pack from 1000 Mile now.Achilles tendon paddingAdditional padded zones on the toes and ball of foot - provide extra comfortArch bracing - gives additional support and a custom fitFlat-toe seam - prevents irritation from the sock along the top of the toes, eliminating friction in this areaVentilation zones on the top of the foot - maximise airflowFabric: Merino wool blendPack of: 2