Up to 50x more robust than a bosch 2607001528 extra hard bitneed robertson screwdriver bits for your next screwdriving job? Bits that last long and perform well in heavy duty applications? Try pro impact r. We designed them for strength and resistence to high torque.pro impact r screwdriver bits are a great choice for installers looking for robust, heavy duty screwdriver bits. The bits are made from heat treated modified steel for outstanding strength and resistance to high torque. Their torsion zone absorbs the torque stress at the bits’ tip to make sure they won’t break. They have colour coded rings indicating the head type and laser markings helping you pick out the size you need.1 4 impact rated hex shank for use in impact driver and drill drivertested in bosch labs according to bosch standard procedures.features and benefitsbull up to 50x more robust than a bosch 2607001528 extra hard bitbull 1 4 impact rated hex shank for use in impact driver and drill driverbull for driving r screws efficiently, eg when installing all types of panels, equipment, and fixturesbull highly efficient for installers, electricians, metalworkers, and woodworkers robustspecificationsdimensions r2length mm 55