Item Name: 4-20mm Hex Coated Core Step Drill Bit Spiral for Hard Stainless Steel Newly. Smart TV Box Android Quad Core HDMI 1080P Wifi Streaming Media Player UK
Features
100% brand new and high quality.
Made from HSS-Co, heat treatment to it, high hardness, high wear resistance, high toughness, high bending strength, sharp edge, the best choice for processing stainless steel, better than ordinary step drill.
Unique step structure, a drill can punch out a variety diameters of holes.
Does not need center punch to assist it, compared with ordinary hemp flower drill, it is stable and difficult to be broken.
It has these functions that hemp flower drill does not have, such as burrs removing, chamfering, punching elliptic hole, etc.
It is suitable for being installed on the pistol drill and bench drill, applicable for punching on these harder workpieces, such as stainless steel, carbon steel, aluminum plate, iron plate, etc.
Specifications
Material:HSS-Co
Surface treatment: TiALN coated
Handle diameter:1/4" Hex shaft
Step quantity:9 steps
Step diameter: 4/6/8/10/12/14/16/18/20mm
Note
Please water it for cooling while punching so that can prolong its lifetime, rotation rate from 550 to 2800(rad/min) is recommended.