Special Features:

Step drill - ass'y frame bomb rack, inb'd; r/h helix

Properties:

An end cutting tool having two or more cutting edges, and having helical flutes or grooves adjacent thereto for the admission of coolant and the ejection of cuttings or chips. It is used for drilling holes in various materials. Excludes drill, masonry (as modified); and drill,twist, bone. See also drill, pivot, jeweler's and drill, hardened steel, carbide tipped.