Ergon GP1 BioKork Bicycle Handle Bar Grips (Cork Brown - Small - GripShift) GP1 series of grips offer maximum comfort and the best possible pressure distribution Cork is the ideal grip material with its natural dampening qualities. Cork is also anti bacterial and hypoallergenic Grip is 40% cork which reduces weight. Inner sleeve is reinforced using natural fibers Gel uses vegetable oil instead of the normal mineral oil 145 grams