Ergon GP1 Bio Kork Performance Grips Ultimate ergonomics for ultimate comfort, Ergon's GP1 Biorkork Performance Grips displays an ecological theme. Ergon constructed the GP1 with 40% cork sourced from sustainable forests in Portugal. Cork offers a dense feel and natural damping qualities while also being also a hypoallergenic and antibacterial material. The inner core is plastic reinforced with natural fiber. Model: Regular, Gripshift, Rohloff/Nexus 100% recyclable aluminum clamp Grip comprised of 40% cork Gel in palm section of the grip is vegetable oil based Recommended usage: Mountain Bike, Touring | Ergon | Gp1 | Biokork | Performance Grips Large, Gripshift