Bosch Hex Shank HSS Step Drill Bit 4mm

The Bosch Hex Shank HSS Step Drill Bit is a versatile stepped drill bit designed to drill multiple hole diameters with a single bit, delivering smooth, burr-free results in thin sheet materials. The split-point tip eliminates the need for pre-punching, allowing for a clean, accurate start without the bit wandering. A CNC ground spiral flute optimises chip removal and reduces vibration, while axial and radial relief grinding ensures consistent cutting performance and a smooth finish throughout each step. This step drill bit is suitable for use on non-ferrous metals, sheet steel, stainless steel, and sheet plastic — making it a practical choice for electricians, fabricators, and engineers working with thin materials. The ¼" hex shank provides a secure, positive connection in both three-jaw chucks and ¼" internal hex tool holders. Laser-marked diameter figures on both spiral flutes remain clearly visible throughout the life of the bit. Features and Benefits: • Drills multiple diameters from 4mm to 20mm with a single bit • Split-point tip for easy, accurate starts without pre-punching • CNC ground spiral flute for optimised chip removal and reduced vibration • Axial and radial relief grinding for consistent cutting performance and smooth finish • ¼" hex shank for secure connection in three-jaw chucks and hex tool holders • HSS construction for long service life — extended further with coolant use • Laser-marked diameter figures on both flutes for easy, durable identification Specifications: Total length: 70.5mm Shank diameter: ¼" (1/4 inch) Step diameter range: 4–20mm Step height: 4mm Material: HSS (High-Speed Steel) Net weight: 0.077kg