The Rooster Supertherm Wet Socks are made out of 4mm Neoprene – designed to keep your feet Super warm!The superstretch neoprene outer allows these socks to span several shoe sizes making it easier for you to find the correct size – a closer fit means warmer feet! Inside the sock there is a super soft, grey marle, quick-dry lining which not only improves the thermal qualities of the sock, it also feels very soft and comfortable next to your skin.The sock is glued and blind-stitched to prevent cold water flushing, with a comfortable seam layout designed to maximize comfort.Features4mm superstretch neopreneGlued & blind stitchedPlush, thermal, quick-dry liningComfortable seam layoutOne sizeWashing InstructionsWe recommend hand washing in warm water.SizingThe material exhibits some stretch and a single sock size will span a number of shoe sizes.EU Shoe SizeUK Shoe Size33 – 361 – 3