The 12-piece set Wera Bit-Check 12 Diamond 1 consists of 11 bits with different profiles and a bit holder Rapidaptor with quick change chuck and 1/4 "hexagon. The 11 BiTorsion bits have a diamond coating to reduce the risk of slipping. Bite The tiny diamond particles to the screws formally in the screw. the BiTorsion system ensures longer service life by the hardness of the shaft opposite the output peak is reduced by about 20% by a targeted tempering process. This torsion zone absorbs higher loads. when BiTorsion holder accepts the integrated torsion smaller loads. in the workplace, can be put down the bit checks, so the tool is always ready to hand.