Irwin 11103 Unibit Step Drill Bit 6-18 Mm Hss

Product Description

The IRWIN 11103 Unibit is a self-starting step drill bit engineered for drilling multiple hole sizes with a single tool. Built from high-speed steel, it steps through sheet metal, thin steel plate, conduit knockout panels, PVC, and similar materials without a center punch or pilot hole. The stepped profile covers a 6 mm to 18 mm diameter range, making it a go-to bit for electricians and HVAC techs who need clean, accurate holes across a range of sizes during rough-in and service work. The 3 flatted shank provides a secure grip in standard drill chucks and reduces the risk of slipping under load.

This step bit is suited for light-gauge sheet metal fabrication, electrical panel work, conduit entry holes, junction box knockouts, and HVAC sheet metal applications. The single-flute geometry clears chips efficiently in thin materials, keeping cuts clean and reducing heat buildup. Packaged as a single bit, it is well matched to individual technicians, service vans, and small shop inventories that need a reliable step bit in the 6 to 18 mm range without redundant tooling.

Key Features

• Self-starting tip eliminates the need for a center punch or pilot hole on most materials
• Steps from 6 mm to 18 mm in a single bit, reducing tool changes
• High-speed steel construction provides durability across repeated use in sheet metal and thin plate
• 3 flatted shank seats securely in drill chucks and prevents rotation under load
• Single-flute design promotes efficient chip evacuation in thin-gauge materials
• Unibit trade name indicates OEM-style design consistent with industry-standard step bit geometry

Compatibility

Designed for use in standard keyed and keyless drill chucks that accept a 3 flatted shank. Suitable for drilling sheet metal, thin steel, aluminum, PVC, and similar thin-gauge materials in electrical, HVAC, and general trade applications.

Installation Notes

This bit is installed by a qualified tradesperson into a compatible power drill or drill press with a chuck rated for the shank size. Secure the workpiece before drilling to prevent spinning or shifting. Apply steady, moderate pressure and allow the bit to step through the material at an appropriate speed for the material type. Inspect the cutting edges before each use and replace the bit if chipping or excessive wear is present.

Technical Specifications

• Material: High-Speed Steel
• Drill Diameter Range: 6 mm to 18 mm
• Number of Flutes: 1
• Shank Configuration: 3 Flatted
• Package Quantity: 1 each

Standard Information

• Brand: IRWIN
• Manufacturer Part Number: 11103