Saiper 6Pcs Drill Tap Combination Bit Set (1/8''-3/8'') With 1/4" Hex Shank, Hss ?NOTE? 1, Not suitable for Hard Metal! 2, Recommended for use on tapping machines to prevent swaying and tilting 3, Pay attention to the operation method when using the hand drill. Excessive sloshing and tilting will affect tapping and even break the tap Product Specifications [Type] Drill Tap Combination Bit Set [Material] High Quality High Speed Steel (HSS 4341) [Measurement System] Inch [Shank] Quick Change 1/4" Hex Shank (6.35mm) [Size] 6 Size 1/8"(3.175mm) 5/32" (3.97mm) 3/16" (4.76mm) 1/4" (6.35mm) 5/16" (7.94mm) 3/8" (9.53mm) Features 1, Made of high quality HSS 4341 for high hardness, rustproof, solid and durability 2, Back tapered beyond tap to prevent thread damage from over-drilling 3, Self-Centering point, do not need assistant center drilling or center punching 4, Greatly save processing steps and time costs, improve working efficiency in hole drilling, tapping, deburring and countersinking 5, Suitable for Low Hardness Materials Such as wood, plastic, aluminum plate, iron and other soft metal (thickness of less than 3mm) Packaging Includes 6pcs * Drill Tap Combination Bit (1/8''-3/8'') ?Imperial Inch Size? 6 sizes in one drill tap combination bit set to meet your diverse requirements with quick change 1/4" hex shank (1/8", 5/32", 3/16", 1/4", 5/16", 3/8") ?High Speed Steel Material? Made of high quality HSS 4341 for high hardness, rustproof, solid and durability. Back tapered beyond tap to prevent thread damage from over-drilling ?Save Time? Complete hole drilling, tapping, deburring and countersinking in one operation and greatly save processing steps and time costs, improve working efficiency ?Self-centering Point? Countersink tap and thread set are recommended for use on tapping machine, which provides better stability against swaying and tilting! ?Notice? Not suitable for Hard Metal! Suitable for fast drilling, tapping machining, cutting on Low Hardness Materials Such as wood, plastic, aluminum plate, iron and other soft metal (thickness of less than 3mm)