【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'')