JCB pack of 4 crew leisure socks with reactive yarn technology which keeps feet fresh, dry and warm all day. Reactive is lighter than polyester and nylon and provides bulk and warmth for less weight. With excellent heat-retaining properties it is warmer than wool. Reactive has a unique hydrophobic nature and antibacterial properties which keeps the wearer dry and warm as it is quick drying and will not absorb water in the fibre. This specialised yarn wicks away water from the skin and through the sock for quick evaporation. These fibres are not attacked by bacteria or micro-organisms, so feet are kept fresh.