•Available in 3mm and 5mm thicknesses. •EverFlex neoprene material on upper portion. EverFlex is an ultra stretch neoprene with enhanced abrasion resistance. EverFlex is used on the inside and outside of the Everflex line of steamers & jackets for maximum comfort, stretch and durability. also used in other models in areas needing 'extra' stretch, like under-arms, back of knees and calves. •Ultra smooth Silverskin lining. Silverskin is an ultra-smooth interior finish. It consists of a cell finish with 'metalite' coating for extra warmth retention. It dries fast and seals extrememly well.