Material: stainless steel Size: The total length: 1.4cm / 0.55inch, the top diameter: 1.1cm / 0.43inch and the bottom diameter: 0.59cm / 0.23inch Packages: 12 Pcs The brake disc rotor screws can help keep the brake discs in place when you put them back on the tire Just use screwdriver (not included) to remove the old screws and install new brake disc rotor screws on