The high spec pull-over that is geared for the hash climates that are encountered in rock and alpine climbing. Nylaz Psiphon delivers superior abrasion resistance, air permeable and stretchy enough for comfort on the move. Helmet compatible provides wind and weather protection and provides a fast one handed adjustment. Every effort has been made to make it as lightweight as possible without compromising on freedom of movement. It packs away to the size of a climbing shoe.