855/1 BTH bits, PZ 2 x 25 mmBiTorsion bits for Pozidriv* screws with Torsion zone. This greatly extends the product service life. This provides the best possible durability together with the matching holder. Extra-hard, hexagon, suitable for holders as per DIN ISO 1173-D 6.3. * Pozidriv = registered trademark of European Industrial Service Ltd.