Milwaukee 48-89-9050 2 Piece 48-89-9100 and 48-89-9110 Step Drill Bit Combo Pack Step drill bit set allows you to quickly and easily drill a variety of round holes in steel, brass, copper, aluminum, wood, Plexiglas and plastic Self-starting multi-hole and hole-enlarging bits with a double-flute design Made from high alloy, industrial grade steel for increased durability Set provides a diameter range from 1/8 to 1 inch Backed by 5-year limited warranty; 2 different drill bits included