HSS Spiral Grooved Step Drill 4-20mm<br /><br />Features :<br />No need for a pilot hole<br />Titanium coated to reduce friction and run cooler<br />High speed steel，durable.<br />HSS Drill Bit Set For Wood， Plastic and Aluminum， Copper， Steel<br />Ideal For DIY， Home and General Building/Engineering Using<br /><br />Specification :<br />Color : Gold (as picture shown)<br />Material : High Speed Steel<br />Surface : Nitrogen treatment (increasing the hardness and abrasion resistance)<br />HSS Spiral Grooved Step Drill 4-20mm<br /><br />Features :<br />No need for a pilot hole<br />Titanium coated to reduce friction and run cooler<br />High speed steel，durable.<br />HSS Drill Bit Set For Wood， Plastic and Aluminum， Copper， Steel<br />Ideal For DIY， Home and General Building/Engineering Using<br /><br />Specification :<br />Color : Gold (as picture shown)<br />Material : High Speed Steel<br />Surface : Nitrogen treatment (increasing the hardness and abrasion resistance)<br />Shank:Triangle round handle<br />Scop : thin iron plate，aluminum，insulation panels，PVC panels 4mm thickness within the timber.<br />Model: 4-20mm(4，6，8，10，12，14，16，18，20mm)，Shank:25 x 7mm<br /><br />Package included :<br />1 x 4-20mm HSS Drill