Impact Pro Black Oxide Drill Bits. Made from premium M2 steel to withstand heat and wear under rigorous drilling applications. One-piece, fully ground construction lasts 6 times longer than two-piece constructed bits. 1/4" quick-change shank fits all quick-change adapters and cordless impact tools. Features. Impact Pro 0.34" Black Oxide Drill Bit. Specifications: Dimension 1 x 4 x 7 inches. Hub 28. Weight: 0.08 lbs