Features of the Castelli Men's Free Aero Race 4 Bibshort - TV Vortex dimpled fabric on legs for aero Performance Forza fabric on inner legs with 38% LycraA(R) content for perfect Fit Stripe mesh engineered minimalist bib construction keeps you cool Giro4 leg gripper elastic for better grip distributed over larger Area Doppio V construction in front for increased support and comfort Flat-lock stitching Progetto X2 Air Seamless seat pad