It is often necessary to remove the crankshaft pulley when replacing the timing belt. The pulley retaining bolt is fitted with a high torque loading and the flywheel must be securely locked during installation/removal. Jamming tools into the teeth of the flywheel will cause serious damage to both teeth and housing. This locking tools securely locates in the teeth and fixes to the housing using manufacturer's guidelines. Suitable for petrol and diesel engines.