Wera 8671 premium plus impaktor diamond bits for torx screws wera 05073967001 this 14in hexagon drive impaktor diamond torx tx40 screw bit from wera is suitable for use with impact screwdrivers and power tools these high strength bits are easily recognisable due to their black colour wera 05073967001 8671 premium plus impaktor diamond bit for torx screws tx40