Spade, auger and wood boring bits: flat spade bits, auger and ship auger bits, self-feed bits, Forstner bits and flexible installer auger bits. Brands include Irwin (Speedbor, Marples), Milwaukee (Speed Feed) and Klein Tools.
Spade bits drill fast rough holes; auger and self-feed bits pull themselves through framing for larger, cleaner holes; Forstner bits cut flat-bottomed holes. Bits are sized by hole diameter, from 1/4 in. to over 2 in. Part of Drill & Driver Bits.
