Twist drill bit Bosch Metal drill bit HSS-G DIN 338 4 mm 2 pcs

The Bosch Metal drill bit HSS-G DIN 338 (4 mm, 2 pcs) is a high-speed steel twist drill designed for precision drilling in a range of metals and some hard plastics. It delivers clean, accurate holes and is suitable for professional metalworking tasks. These HSS-G drill bits come with a split point tip for reliable centring and are available in Topline and standard qualities to match different performance requirements.

Advantages

Precision-ground HSS-G geometry enables up to 40% faster drilling and up to 50% lower feed pressure compared with standard-ground HSS drill bits that use a chisel edge. The self-centring split point eliminates the need for pre-punching or pilot drilling for holes up to 10 mm in diameter. Available in two qualities—Topline for the highest demands and standard for professional use—these drill bits combine durability and consistent cutting performance.

Suitable for

• Alloyed and non-alloyed steel with tensile strength up to 900 N/mm²
• Cast steel and cast iron
• Sintered iron and malleable cast iron
• Non-ferrous metals (e.g., aluminium, copper alloys)
• Hard plastics

Key specifications

• Brand: Bosch
• Type: HSS-G twist drill, DIN 338
• Diameter: 4 mm
• Pack size: 2 pieces
• MPN: 2608585916
• EAN: 3165140521512

How to use

Mark the drilling point and secure the workpiece to prevent movement. Use appropriate cutting fluid for metallic materials to extend tool life and improve chip evacuation. Start drilling at moderate speed; the split point will centre without a pilot hole for diameters up to 10 mm. Apply steady feed pressure—reduced compared with standard HSS drills—until the hole is completed, then withdraw the drill while rotating to clear chips.

Recommendations

For best results in steel and cast materials, use suitable cutting lubricant and a drill press or guide when possible. Select the Topline quality for high-frequency or demanding applications and the standard quality for routine professional work.