BiTorsion bits for Pozidriv* screws with an elastic torsion zone, which transfers kinetic energy during peak loads. With a softer bi-torsion zone to prevent the bit tip twisting under high loads. This extends the life of the product considerably. The right holder will maximise the life of your bits. Extra hard design. 1/4'' hexagonal, for holders according to DIN ISO 1173-D 6.3.