Wera impaktor tri torsion system diamond coated anti cam out screwdriver bits are specifically designed for cordless impact drivers and suited to the heaviest duty screwdriving jobs precision hardened to allow the metal to flex in a control area and absorb the stresses applied by constant use in heavy duty impact drivers due to this unique hardening process the life of the screwdriver bit is dramatically improved the impaktor system is unrivalled in performance extremely hard wearing pre