Drill bit Bosch 2608900257, HSS metal drill, 4 mm diameter

Straight-shank 4 mm HSS metal drill bit by Bosch. This 4 mm diameter drill bit is made from high-speed steel (HSS) and is intended for drilling metal and other materials suited to HSS tooling. The straight shaft fits standard chucks and handheld or bench drills that accept a 4 mm shank, providing a compact option for creating precise small-diameter holes in maintenance, workshop and DIY applications.

Advantages

The HSS composition offers good hardness and heat resistance for cutting metal, maintaining edge retention under typical drilling speeds. The straight shank provides secure clamping in standard chucks and allows use in a wide range of portable and stationary drilling machines. Its 4 mm diameter enables accurate, repeatable small holes while occupying minimal space in a tool kit. Bosch manufacturing ensures dimensional consistency and predictable performance for typical metal drilling tasks.

Suitable for

• Drilling holes in steel and non-ferrous metals
• General workshop and maintenance drilling
• Precision DIY projects requiring small-diameter holes
• Use with handheld drills and drill presses that accept a 4 mm shank

Key specifications

• Material: High-speed steel (HSS)
• Shank type: Straight shank
• Diameter: 4 mm
• Intended application: Metal and other HSS-suitable materials
• Compatibility: Standard chucks accepting 4 mm shank

How to use

Select an appropriate drill speed and secure the workpiece before starting. Clamp the 4 mm straight-shank bit firmly in the drill chuck, ensuring it is centered and tightened. For metal drilling, mark the drilling point and consider using a center punch to prevent walking. Use steady pressure and allow the HSS bit to cut without forcing; withdraw periodically to clear chips and reduce heat build-up. Apply cutting fluid when drilling harder metals to extend tool life and improve finish.

Recommendations

For best results when drilling metal, start with a moderate speed and increase only if the bit and material allow. Use light cutting oil for steel and harder alloys. Replace the bit when wear or chipping affects hole quality, and match drill speeds and lubrication to the specific material being drilled.