IRWIN 73827 Jobber Drill Bit, Spiral Flute, 3-15/16 in L Flute, Reduced Shank, 27/64 in Dia x 1-4/9 in L Shank | M-2 high-speed steel for strength, heat resistance, and wear resistance in general drilling of wood, metal, and plastic. The 3/8 in reduced shank fits all 3/8 in drills. Jobber length.