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Step Drill Bit (HSS)

Catalog (SKU) Number: AT-ST

Irwin Unibits come in various sizes and step quantities. These bits save time by eliminating the need to change drills when drilling round holes in thin materials. Each smaller size drill also acts as a pilot for the next size. Patented single-flute cutting edge gives greater control through steps and a true round hole every time. Ideal for drilling holes into thin materials such as stainless steel, copper, brass, aluminum, plastic and laminates. SpeedPoint tip penetrates faster than previous Unibits and prevents walking. 3-faltted hex shank prevents slipping in drill chuck. Drill diameters etched in flute for easy identification.

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Product Specifications

Step-Drill Bits  
Part NumberShankSize Range
AT-102311/41/8 to 1/2
AT-102321/43/16 to 1/2
AT-102333/81/4 to 3/4

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Rotary Hammers are an essential tool, when breaking up, building or generally working with concrete. Here are a few uncommon tips and tricks that will help the tool, bit, and operator. Let the weight of the tool do the work for you; pressing the tool with a large amount of force just leads to exhaustion. Routine maintenance prevents early and preventable mechanical failures from occurring; Grease the shank of the bit every time you change it. You can use your rotary hammer as a heavy duty drill by setting it to the “drill only” setting.

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