Features: CNC aluminum alloy mountain bike color crank cover BB central axis screw sprocket specifications Aluminum alloy CNC machining, precision & strength, much better than the original plastic screws. Various colors, suitable for personality modification. parameter： Size: M18/M19/M20 Material: Aluminum Alloy Weight: 7g Color:Black,Red,Blue,Rainbow color M18 threaded screws are suitable for PROWHEEL hollow one chain ring FS.A crankset and the old FC 4500 and FC 5600 highway cranksets, etc. Crankset etc. M19 threaded screws are suitable for IXF, LEBYCLE and other brands of hollow integrated crankset M20 crank cover screw for Shiman0 kit Such as: M4000, M590, M596, M661, SLX, XT, XTR and other integrated chainrings If you are not sure about the specifications, please measure by yourself. Package includes: 1pc Crank Bolt Cover Cap