Shipping weight for this item is 0.8 ounces
- TightFit® threaded shank drill bits are made of M2 or M7 high-speed steel, for drilling hard, tough materials.
- With a 135 degree split-point, 1/4-28 threaded shank and a 5/16" hex adapter for easy removal.
- Three lengths of drill bits: LONGS=2 1/8"; SHORTS=1 1/4"; and STUBS=1/2-5/8" (excluding the threads).
- TightFit® threaded shank drill bits are black oxided to add lubricity, prevent corrosion while enhancing appearance.
- These drill bits comply with National Aerospace Standards.
The drill bit complies with National Aerospace Standards. The Standard provides the following description, "A special short flute, heavy duty drill designed for drilling the hard, high strength alloys used in aircraft manufacturing." The drill bits are made from M2 or M7 tool steel with self-centering, 135 degree, P3 split points and a Rockwell C scale hardness of 63.5 to 66. They are manufactured as right-hand tools with 5/16" hex wrench flats and 1/4-28 UNF-2A external threads. TightFit® threaded shank drill bits are concentric, self-tightening, non-slipping, long life tools designed for work in limited space situations. The decimal size of a #21 is 0.1570".
TightFit® threaded shank drill bits WORK EQUALLY WELL IN METAL, WOOD OR PLASTIC.
Before ordering please select the length of drill bit you require. The drill bit is available in three lengths: LONG = 2 1/8"; SHORT = 1 1/4"; and STUB = 1/2-5/8" (threads not included in overall measurement).