Challenge Grifo tires are the standard by which others are judged. A dependable tread that has been ridden to countless victories over the years. Challenge Grifo’s are simply one of the finest tires you can choose. Identical tread to Grifo handmade open tubular and has a Vulcanized 120 tpi nylon casing tire with kevlar folding bead 700x32mm. Don’t forget to add some Quality Tubes to your order.