[name] bicycle expansion screw [material] aluminum alloy [Specification] for front fork head tube of 25.4-28.6 diameter [description] a fork head tube of carbon fiber is generally must use， aluminum alloy or steel head tube of the front fork can also use. [Characteristics] can be used repeatedly Bowl group can match various shape of the cover， of course， if you are the original car bowl set cover more beautiful， he is also the perfect compatible.