Advantage: Up to 5 times faster than standard bi-metal hole saw for drill wood. Up to 10 times more cuts than standard bi-metal hole saw for drill wood. Replaced the following drill bits: spade bit, forstner bit, auger bit, bi-metal hole saw, diamond hole saw. Max cutting depth: 6.6” (167 mm). Ideal drill for multiple materials: hard wood (not with nail), hardy plank, MDF, fiberglass, wall tile, air brick, plasterboard, for thick wall, roof. Note: Cutting material hardness: Not up to 6. For use in standard rotary drills, not for use in hammer mode. Package: 1 of 3” 76 mm hole saw cutter (red or black), 1 of mandrel for 1/2” chuck, 3 of pilot drill bits. The silver one is for wood. The carbide tipped one is for stone. The rod one is guide. Ideal drill for multiple materials for hard wood (not with nail), hardy plank, MDF, fiberglass, wall tile, air brick, plasterboard, for thick wall, roof.