High-quality bits made of stainless steel for internal TORX screws. Wera stainless steel tools are manufactured from stainless steel, preventing unsightly foreign rust. With a torsion zone: Torsion bits absorb torque peaks in the torsion zone. This prevents premature wear and extends the lifespan of the bit. 1/4" hexagon, compatible with holders according to DIN ISO 1173-D 6.3.