A proprietary cryogenic hardening process hardens to the core and has up to a 50% longer life. Optimized tooth form for up to 2X faster cutting and wide, angled, and offset slots for easy plug access. For use with steel, non-ferrous metals, wood, plastic. Set includes (11) hole saws: 3/4 in., 7/8 in., 1 in., 1-1/8 in., 1-3/8 in., 1-1/2 in., 1-3/4 in., 2 in., 2-1/8 in., 2-1/4 in., 2-1/2 in., (2) arbors with pilot bits, (2) pilot bits, (1) adapter, and (1) spacer. Room for additional hole saw and arbor storage.