Wera Diamond Coated 851/1 BDC Phillip #2 Insert Bit, 1/4-Inch Drive BiTorsion Diamond Coated 1/4" hex drive Phillips insert bit, PH2 x 1" BDC diamond coated bits bite into fastener ensuring a secure fit and reduce cam-out effect Special tempered zone reduces risk of breakage and significantly extends life of bit Partner with BiTorsion bit holder for optimal performance Limited Lifetime Warranty, German Engineered