Hertel SDD43274901 Step Drill Bit 4-12 Mm 9 Sizes Hss

Product Description

The HERTEL SDD43274901 is a high-speed steel step drill bit designed to drill and step-ream multiple hole diameters in a single tool. It covers nine hole sizes from 4 mm to 12 mm in 5 mm step increments, eliminating the need to swap bits between passes. The round shank with three flats measures 6.5 mm in diameter and seats securely in standard drill chucks and drivers. The bright, uncoated finish is suited for general-purpose drilling in sheet metal, thin steel, aluminum, and plastics. Machinists, HVAC technicians, and electricians use this bit for punching clean, consistent knockout holes in panels and enclosures.

This step drill bit fits common drill press, cordless drill, and right-angle drill setups where a compact, multi-size tool is needed in tight work areas. It is well suited for light-gauge sheet metal work in HVAC ductwork fabrication, electrical panel knockout drilling, and plumbing rough-in work where panel penetrations are required. The 5 mm step length provides a defined cutting shoulder that leaves clean, burr-minimized holes without the need for a separate deburring step in many materials.

Key Features

• Nine hole sizes in one bit, ranging from 4 mm minimum to 12 mm maximum diameter
• 5 mm step length for defined cutting shoulders and clean hole edges
• High-speed steel construction for durability across steel, aluminum, and plastic substrates
• Round shank with three flats prevents slipping in chuck jaws
• 6.5 mm shank diameter fits standard keyless and keyed drill chucks
• Bright uncoated finish for easy visual inspection of cutting edge condition

Compatibility

Designed as a general-purpose step drill bit compatible with standard drill presses, cordless drills, and hand drills accepting a 6.5 mm round shank with flats. Suitable for drilling light-gauge sheet metal, aluminum sheet, and plastics up to 12 mm hole diameter.

Installation Notes

This bit is installed and used by machinists, HVAC technicians, electricians, and plumbers performing panel or sheet metal drilling. Secure the shank fully in the chuck and confirm the flats are engaged before drilling. Apply consistent feed pressure and use a cutting fluid or lubricant when drilling ferrous sheet metal to extend cutting edge life. Wear appropriate eye and hand protection per applicable shop safety standards.