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″, 7/8″, 1″, 1-1/8″, 1-3/8″, 1-1/2″, 1-3/4″, 2″, 2-1/8″, 2-1/4″, 2-1/2″, (2) arbors with pilot bits, (2) pilot bits, (1) adapter, and (1) spacer. Room for additional hole saw and arbor storage.