Specification: Color: Sliver Material: Aluminum Alloy Steel Size: fit for 28.6mm1-1/8"" Headset star nut Application: steel / aluminum alloy / titanium alloy front fork with an outer diameter of 28.6mm at the upper end (all carbon front forks can not be used) Features: simple operation , automatic positioning of left and right and depth of the flower core Instructions for use Steps: 1. After the front fork is cut off, the edge of the vertical tube is squeezed with force, and the edge is twisted out. Before entering the sunflower, use a file to buff the edge to prevent the sleeve from binding. 2. Unscrew the steel sunflower and screw to the end; 3. Put the sleeve on and prepare to break in. 4. Use a rubber mallet to hit the ejector rod until it is flush with the sleeve. 5. Remove the sleeve and ejector rod, and the drivetrain is complete. Package Included 1 Set of Bike Clevis Installer Free Replacement Special Bolt and 1 Free Starting Nut