This set of titanium plated drill bits contains 5 pieces. Sizes include: 1.5, 2.5, 3.2, 4.0, and 4.8mm. These are high speed steel bits, with 1/4" hex shanks, compatible with cordless power tools. They have been heat treated for maximum durability. Set Of 5 Sizes Of Titanium Plated, High Speed Bits- Heat Treated For Durability Metric Sizes 1.5, 2.5, 3.2 4 And 4.8mm, Each Is Equipped With A 1/4 Inch Hex Shank These Titanium Drill Bits Are Suitable For Use With High Speed Drills, And Cordless Tools Titanium Drill Bits Are Known For Their Incredible Strength And Durability This Set Includes Five Of The Most Popular Sizes In Metric Only