The MILWAUKEE® 3-Piece Cobalt Step Drill Bit Set Cobalt Step Drill Bits are engineered to deliver up to 15X the life in stainless compared to current solutions and up to 1000 holes in mild steel. The Cobalt Step Drill Bits are recommended up to 14ga. The elongated dual-flute design also offers the best heat management combined with the smaller steps for smoothest drilling experience and a Rapid Strike™ tip that allows for 2X faster starts in stainless. Made in the USA with global materials, these step bits have best-in-class performance in cordless drills used on low-speed in Stainless Steel and high speed for mild steel.