Thunderbolt® Drill Bit Set, 14 Pieces, High Speed SteelIncludes: (1) 1 16", (1) (1) 5 64", (1) (1) 3 32", (1) (1) 7 64", (1) (2) 1 8", (1) (1) 9 64", (1) (1) 5 32", (1) (1) 3 16", (1) (1) 7 32", (1) (1) 1 4", (1) (1) 5 16", (1) (1) 3 8" , (1) (1) 1 2" Titanium coating reduces heat build up for up to 3X longer life 135 split point tip starts on contact to prevent walking, (1) while the parabolic flute clears chips fast Thicker web provides greater strength No. of Pieces: 14 Material: High Speed Steel