Wera 8554 impaktor diamond bit for pozidriv screws 50mm wera 05073961001 this 14in hexagon drive impaktor diamond square pozidriv pz2 bit from wera is suitable for use with impact screwdrivers these high strength bits are easily recognisable due to their black colour wera 05073961001 8554 impaktor diamond bit for pozidriv screws pz2 x 50mm