RUKO FLS-DIN373-HSS-TiN-M10x Counterbore with Pilot, M10, HSS-TiN

When a standard twist drill leaves a cone-shaped bottom, a counterbore with pilot creates a flat-bottomed recess for socket head cap screws. The RUKO FLS-DIN373-HSS-TiN-M10x is engineered to produce precise counterbores for M10 screws in steel, cast iron, non-ferrous metals, and plastics.

Who is it for

Machinists, metalworkers, and maintenance technicians who need clean, repeatable counterbores in production or repair work. The pilot guides the tool into a pre-drilled hole, ensuring concentricity and preventing chatter.

Main features

• DIN 373 geometry: pilot diameter 10.2 mm, counterbore diameter 17.5 mm, shank diameter 10 mm.
• High-speed steel (HSS) body with titanium nitride (TiN) coating for increased surface hardness and reduced friction.
• Three flutes with right-hand cutting direction for efficient chip evacuation.
• Cylindrical shank fits standard drill chucks and collets.
• Ground profile for accurate cutting edges and long tool life.

Specifications

• Tool standard: DIN 373
• Material: HSS
• Coating: TiN
• Intended screw size: M10
• Pilot diameter (d1): 10.2 mm
• Counterbore diameter (d2): 17.5 mm
• Shank diameter (d3): 10 mm
• Overall length (l1): 80 mm
• Pilot length (l2): 12 mm
• Shank type: Cylindrical
• Number of flutes: 3
• Cutting direction: Right-hand cut
• Tool type: Counterbore
• Suitable for: Steel, cast iron, non-ferrous metals, plastics
• Surface finish: Bright with TiN coating
• Manufacturing process: Ground profile

Tips

Pre-drill the pilot hole to 10.2 mm diameter. Use cutting fluid for steel and cast iron to improve finish and tool life. For plastics, reduce speed to avoid melting.