Detailed Product Description Multi-purpose Masonry Drill Bits1. We could produce according ... . Flute type L, U, W etc produced by CNC machine, high function self-protection tip welding ... . Surface treatment: Sand-washed, electrophoresis etc, could drill holes on cement, block, granite, and other stone ... with hammer drills.6. Using impact drill with SDS, or SDS adapter, drilling on granite ...