The new and innovative Multi-Step Reamer step drill makes enlarging holes easy and with consistent quality. 1/2" step thickness makes enlarging holes in sheet metal or even 1/2" metal plate a breeze. Ideal for enlarging or aligning stacked plates or pieces of metal up to a combined thickness of 1/2". Plus, the 3/8" shank with three flats makes using the Multi-Step Reamer step drill in drill chucks easy. Reamers will not slip! Available in three individual sizes, with five steps each, ranging from 5/16" to 1-1/16" diameter.