Drill Bits Clarkson Osborn 29 Piece Mechanic Length Drill Set, Trades Pak, DF15229 7000127699 Extra thick backplate minimizes vibration Extra thick backplate minimizes vibration 8 inches – come stacked flat in the box and are so sturdy that they can often be used more than once (once you’ve used them a few times more stability less breakage for hand drilling applications 3 flats shank to reduce slippage in drill chuck * Black & Gold surface treatment for maximum lubricity and wear resistance Size range 1 16” to 1 2” (by 64ths) Premium HSS substrate 135º Split Point ensures ease of penetration and reduces “walking” when starting a hole Mechanics Length shorter than Jobber length