RUKO KES-DIN335-HSS-90°-6.3mm Countersink Bit, HSS-E Cobalt, 90°, 6.3mm Cutting Diameter

Precision-ground 90° countersink bit in HSS-E cobalt steel, DIN 335 C, with a 6.3 mm cutting diameter and 3 flutes for clean, chatter-free chamfering in tough materials.

Overview

The RUKO KES-DIN335-HSS-90°-6.3mm is a high-performance countersink bit engineered for deburring, chamfering, and countersinking in steel, stainless steel, cast iron, non-ferrous metals, and plastics. Its 90° cutting angle matches standard countersunk screw heads, ensuring flush seating. Made from HSS-E (cobalt high-speed steel), it offers high heat and wear resistance for extended tool life. The bright, uncoated finish and ground profile deliver smooth cutting action. A cylindrical shank with h8 tolerance provides secure chucking. Overall length: 45 mm; shank diameter: 6 mm; 3 flutes; right-hand cut.

What stands out

• HSS-E cobalt steel for high heat and wear resistance
• DIN 335 C standard geometry for reliable performance
• 90° cutting angle for standard countersunk screws
• 3-flute design for smooth, vibration-free cutting
• Bright finish and ground profile for precise results

Technical details

• Tool type: Countersink
• Material: HSS-E (cobalt high-speed steel)
• Standard: DIN 335 C
• Cutting angle: 90°
• Cutting diameter (D1): 6.3 mm
• Shank diameter (D2): 6 mm
• Overall length (L1): 45 mm
• Number of flutes: 3
• Shank type: Cylindrical
• Shank tolerance: h8
• Direction of cut: Right-hand
• Surface finish: Bright (uncoated)
• Manufacturing method: Ground profile
• Suitable materials: Steel, stainless steel, cast iron, non-ferrous metals, plastics

Our verdict

A professional-grade countersink bit that delivers clean, accurate chamfers in demanding materials. The cobalt steel construction and precise grinding make it a reliable choice for workshops and production environments.