The castelli evoluzione 2 bibshorts while this short sits at the entry level of castelli39s shorts range it39s engineered with top level performance it starts with the prodry soft two layer fabric that knits a polyester inner layer with a nylon outer layer for exceptional moisture management and durability then the side panel and leg ending are extra stretchy for exceptional fit the kiss air seat pad is the choice of some of our pro athletes and even sees duty at the tour de fran