Bosch 3 Piece HSS Step Drill Bit Set

The Bosch 3 Piece HSS Step Drill Bit Set is a versatile collection of stepped drill bits designed for smooth, burr-free drilling across multiple diameters without needing to change bits.

Each bit in the set features a split-point tip that allows for an easy, accurate start without pre-punching, making them particularly well-suited for work on thin materials including sheet steel, stainless steel, non-ferrous metals, and sheet plastic. The CNC ground spiral flute design optimises chip removal and reduces vibration, contributing to consistently clean, round holes.

Axial and radial relief grinding delivers high cutting performance and exceptional smoothness throughout the drilling process. The 3-flat shank prevents slipping in the chuck, while laser-marked diameter figures in both spiral flutes provide clear, durable readings during use. Each bit is manufactured from HSS (high-speed steel), offering extended service life when used with coolant.

The set covers a broad range of diameters — from 4mm through to 30mm across the three bits — making it a practical choice for electricians, fabricators, and contractors who regularly drill or enlarge holes in sheet materials.

Features and Benefits:
• Three HSS step drill bits covering step diameter ranges of 4–12mm, 4–20mm, and 6–30mm
• Split-point tip for easy starting without pre-punching
• CNC ground spiral flute for optimised chip removal and reduced vibration
• Axial and radial relief grinding for high cutting performance and smooth results
• 3-flat shank prevents slipping in the chuck of rotary drills and drivers
• Laser-marked diameter figures in both spiral flutes for clear, durable identification
• HSS construction offers long service life when used with coolant

Specifications:
Version: HSS
Total length: 66.5mm | 70.5mm | 93.5mm
Shank diameter: 6mm | 8mm | 10mm
Step height: 4mm (all bits)
Step diameter range: 4–12mm | 4–20mm | 6–30mm
Net weight: 0.365kg

Contents:
HSS step drill bit: 4–12mm step diameter, 6mm shank diameter
HSS step drill bit: 4–20mm step diameter, 8mm shank diameter
HSS step drill bit: 6–30mm step diameter, 10mm shank diameter