Description 33 impact rings made of extremely shockproof plastic. 3 strike pipes made of anodized aluminum. 1 Non-rebounding hammer. Advantage The combination of impact ring and impact sleeve required for the installation of the ball bearing can be found in the table inside the case cover. The axes, bearing casings and gaskets of the bearing will not be damaged. The impact rings have a rubber ring and ensure locking at the strike pipe. For use on ISO bearings with bore dimensions between 10mm and 50mm and outside diameters of 26mm to 110mm.