Viking VF21 Radiantex Boot Liner. New and improved fit. Thicker material for better comfort and wear. Taller in length for improved cold protection. Nylon knit heel protector for stronger wear resistance. Designed to fit all Viking handcrafted rubber boots. Polypropylene and natural synthetic fibres blended with a Radiantex layer for extra warmth (up to -30C). The Radiantex metallized membrane acts as a thermal reflector an dmoisture barrier keeping body heat in and allowing perspiration vapours to escape. Front elastic holds lining in position. Sole features outside seams for a comfortable fit. Note: add 2 sizes to your boot size. ie: if you are a size 10, you would order a size 10 liner and a size 12 boot. Available in sizes 7-15. Sold as pairs.