MIBRO 871570 Titanium Extra Life Metal Master Drill Bit Set, 17 Pieces Quality Titanium Nitride coated high speed steel bits for a long service life- up to 6 times longer 135 degree split points eliminate "skating" on hard materials and doesn't require a center punch All sizes 3/16-Inch and larger have 3 flats on the shaft to prevent slipping in the drill chuck Convenient durable storage case with easy access tilt out inserts