The ideal spare part if you want to use the Bobike GO on two different bicycles. Ideal for commuting. Fits frames with a diameter between 28 - 40 mm. Requires an available length on the frame of 105 mm to be installed. Fits round and oval tubes, and was designed to accomodate the brake cable, preventing it from being pinched. Inside, a rubber pad will prevent the frame from getting damaged. tools included.