The RS PRO 131‑842 is a precision-engineered high-speed steel (HSS) counterbore drill bit designed for creating flat-bottomed recesses to accommodate M5 threaded screws flush with a workpiece’s surface. It features a 10 mm cutter diameter with an 18 mm cutting length, an 8 mm plain shank, and an overall length of 80 mm. Ideal for metalworking tasks that require discreet screw heads, this single-piece tool offers reliable, entry-level functionality for both professional and workshop environments.

Why choose the RS PRO HSS Counterbore Drill Bit?

RS PRO’s HSS counterbore bits, including the 131‑842, provide excellent wear resistance and durability thanks to their high-quality HSS construction. They maintain sharpness over prolonged use, ensuring consistent, clean cuts and smooth finishes. 

Standout Features of the 131‑842 Counterbore Drill Bit:

• High-quality HSS material 
• 10 mm cutter diameter with 18 mm cutting depth 
• 80 mm overall length; 8 mm plain shank 
• Pilot diameter 5.5 mm 
• Designed for flush/undercut countersinking.