Irwin Industrial Tools 10228 Unibit 228 Step Drill Bit Set 4-Piece
Irwin's Unibit SpeedPoint combines the most desired features of a Step Drill, speed and control and as many as 13 different sizes onto one single-fluted step drill bit. Irwin Industrial Tools 10228 2284-Piece Set (10231, 10232, 10234, 15101)