PORTER-CABLE PC3700 Hole Saw Set, 7-Piece Made of high carbon steel which is ideal for fast cutting in wood Optimized tooth design provides fast cuts and long life 1/4-Inch hex shank mandrel for use with quick-change adapters Includes 1", 1-1/8", 1-1/4", 1-1/2", 1-3/4" and 2" hole saw and a 1/4" shank mandrel