Bosch Co14B 14-Piece Assorted Set With Included Case - Cobalt M42, Gauge Metal BOSCH Cobalt M42 metal drill bits are engineered with upgraded M42 alloy, containing 8% cobalt. These hard-core Cobalt bits deliver 10x life vs. Standard bits, are jobber length and withstand high-heat applications. The thick web-helix design delivers fast material removal and increased stability. Bits that are 1/8 in. And larger feature a split point; bits 3/16 in. And larger feature a three-flat shank, for better bit grip. These Cobalt drill bits provide superior performance in stainless steel and can be used to drill cast iron, titanium and other hard or abrasive metals. Cobalt M42 drill bit ? provides upgraded M42 Cobalt jobber-length bits designed for durability, high heat resistance and Hardened surface for stainless steel, cast iron, titanium, light-gauge metal and aluminum Enhanced M42 alloy material ? contains 8% Cobalt alloy that delivers 10x life vs. Standard bits High-heat resistant bits ? withstand high-temperature applications for extended periods of time Thick web-helix design ? provides additional stability in tough applications Surface-hardened tip ? penetrates tough abrasive materials Includes ? 1/16", 5/64", 3/32", 7/64", 1/8", 9/64", 5/32", 3/16", 7/32", 1/4", 5/16", 3/8", 1/2"