Description: - The main body made of aluminum alloy, light weight and high strength. - Easy to remove and insert. - Can be extended to increase 22mm. - If you want to change the small wheel into a big wheel,the brake can solved the position. - Brake adapter for:14 inch modified 16 inch/16 inch modified 18 inch/18 inch modified 20 inch/20 inch changed 451 wheel set.Specification: - Material: Aluminum Alloy - Size:42 x 22 x 10mm/1.7 x 0.89 x 0.4inchPackage Includes:2 Pieces V Brake Extension2 Pieces M10 Screws2 Pieces V-brake Frame ScrewNote:This is only be used to modify a wheel,if you need to modify front and rear, you need to buy two sets.Color may be slightly different due to diffrent monitor.