Hertel SDD43274679 Step Drill Bit 12 Hole Sizes

Product Description

The HERTEL SDD43274679 is a high-speed steel step drill bit designed to drill multiple hole sizes with a single tool. It features a titanium nitride (TiN) coating that increases surface hardness and extends cutting life in ferrous and non-ferrous materials. The 3/8 inch round shank with three flats resists rotation in the chuck and suits most standard drill drivers and drill presses. With 12 hole sizes and a 1/8 inch step length, the bit steps cleanly from one diameter to the next, reducing the need for multiple individual bits. Electricians, HVAC technicians, and plumbers use this type of bit regularly for sheet metal, electrical enclosures, and panel knockouts.

This step drill bit covers hole diameters from 3/16 inch up to 7/8 inch in 1/8 inch increments, making it well suited for sheet metal work, electrical panel entry points, conduit knockout preparation, and thin-wall tubing. It is a common tool for residential and light commercial rough-in work where a range of hole sizes is needed across metal substrates without tool changes. The 3-flat shank provides a secure grip in keyed or keyless chucks throughout the drilling sequence.

Key Features

• High-speed steel construction for durability in metal drilling applications
• Titanium nitride (TiN) coating improves surface hardness and reduces friction at the cutting edge
• 12 hole sizes in a single bit, from 3/16 inch to 7/8 inch
• 1/8 inch step length provides precise, incremental diameter progression
• 3/8 inch round shank with 3 flats prevents chuck slippage
• Compact profile at approximately 3.27 inches in length

Compatibility

Designed as a general-purpose step drill bit for use in standard 3/8 inch or larger keyed and keyless drill chucks on corded or cordless drill drivers and drill presses compatible with round-with-flats shank tooling.

Installation Notes

This bit is installed and used by electricians, HVAC technicians, and plumbers working with sheet metal, enclosures, and thin-wall materials. Always secure the workpiece before drilling and use appropriate eye protection and cutting fluid when drilling harder metals. Ensure the drill chuck is fully tightened on the 3-flat shank before operation. Follow applicable safety standards for hand-held power tool use in the trade environment.