Clip the disc brake alignment tool anywhere on the of disc rotor and turn the disc brake space alignment tool to the position where the disc brake caliper are installed.Press the brake lever tight,Lock tight the caliper screw and release the brake lever.Put the caliper back,lock the screw, but do not make it tight, Press the brake lever repeatedly.Remove the disc brake caliper from the mount.Rotate the disc rotor and remove the disc brake space alignment tool.Colour:greenMaterial:Engineering plasticsPackage Contents:2 * bicycle brake adjustment blockOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.