The GP Series helps prevent numb fingers, aching hands and forearms. The worldwide leader in function, material and craftsmanship. Combining ergonomics, function, and sustainability, the GP1 BioKork has is a top-rated grip and a consumer favorite. The grip is made from 40% cork, sourced from sustainable forests in Portugal. This green, sustainable theme is echoed throughout the complete construction of the grip with an inner core made of a reinforced plastic utilizing natural fibers which makes up 20% of its mass. (Carbon bar compatible)