Bit-Check 7 PZ Diamond 1, 7 pieces 1x 889/4/1 K Rapidaptor Universal Bit Holder: 1/4", x 50 mm 6x 855/1 BDC bits: 2x PZ 1x25 mm, 3x PZ 2x25 mm, PZ 3x25 mmBits with tiny diamond particles on the bit tip. This ensures a secure fit in the screw head, reduces the contact pressure required and lowers the risk of slipping. BiTorsion bits with a torsion zone -