The tifosi tyrant 20 sunglasses frame is made of a grilamid tr90 material which is a homopolyamide nylon which has bending characteristics for flexibility a low density and a high resistance to uv and chemical damage for protection from the sun39s harmful rays these tifosi cycling sunglasses also use a hydrophilic rubber on the ear and nose pieces which can be easily adjusted to give a customised fit for an optimal fit the rubber also increases its grip the more you sweat ensuring the gl