Drill bit Proline 12 mm, model 71240, length 400 mm, single piece

Proline drill bit 12 mm model 71240 is a single-piece, long-reach metal drill bit with a total length of 400 mm. Designed for drilling through metal and other hard materials, it fits standard chucks and is intended for workshop, construction and industrial use where extended reach is required. The drill bit features a double-twist design and a four-blade insert geometry that aid chip evacuation and stability during drilling into dense substrates.

Advantages

The 12 mm Proline drill bit combines extended length with a rigid single-piece construction to enable deep or hard-to-access drilling without the need for extensions. The double-twist flutes promote faster chip removal, while the four-blade insert with optimised geometry improves cutting efficiency and helps maintain a straighter bore. Compatibility with standard chucks allows use with common drills and drill drivers.

Suitable for

• Drilling through metal sheets, structural steel and similar hard materials
• Creating deep or hard-to-reach holes in workshop and construction environments
• Industrial and professional applications requiring extended-reach drilling
• Use with drills that accept 12 mm bits and standard chucks

Key specifications

• Diameter: 12 mm
• Overall length: 400 mm
• Quantity: single piece
• Design: double-twist flutes with four-blade insert geometry
• Intended materials: metal and other hard substrates

How to use

Mount the 12 mm Proline bit securely in a compatible drill chuck. Select an appropriate rotational speed and feed rate for the material being drilled; reduce speed for harder metals to avoid overheating. Apply steady axial pressure and allow the bit to cut without excessive force. Periodically withdraw the bit to clear chips and ensure effective cooling, and use cutting fluid as appropriate for metalworking to extend tool life.

Usage recommendations

For best results when drilling hard metals, use light cutting fluid and moderate speed, and check chuck tightness before operation. Inspect the bit for wear or damage after extended use and replace when cutting performance degrades.