DOYOUNG 4-42mm HSS for Titanium Coated Step Drill Bit Drilling Power Tool for Metal High Speed Steel Wood Hole Cutter Cone

100percent brand new and high quality Features: Unique ladder structure it can open multiple aperture. It can deburr chamfer and open hole but ordinary twist drill can t. Little rock it can carve out a nice aperture without firstly using a center punch. Water to make ti cool while working it can effectively extend the service life. Deburring chamfering elliptical hole enlargement twist drills drills table drills. Widely used to cut holes in a variety of material like steel wood thin iron aluminum alloy insulation boards PVC sheet ect. Recommended drilling speed 250--400 rpm. Suit for use in hardness under 25° artifacts The plate thickness under 5mm. Step Drill Bit only other accessories demo in the picture is not included. Specifications: Material: HSS Size: app.app.10x98mm/0.39x3.86in Style: 4-42mm（4 6 9 12 15 18 21 24 27 30 33 36 39 42mm） Color: Golden Quantity: 1 Pc Note: No retail package. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors the picture may not reflect the actual color of the item. Thank you! Package Includes: 1 x Step Drill Bit