JBO Thread Ring Gauge (NoGo) - Metric Coarse - Right Hand - 6h - M42 x 4.5 FHH Its left-hand spiral flute paired

Its left-hand spiral flute paired with right-hand cutting delivers stable cutting action and efficient chip evacuation for a cleaner finish

and reduced downtime across precision milling and small-tool applications

13 mm bore with repeatable size control

The combination of HSS (M2) material and a left-hand spiral flute with right-hand cutting provides durable performance and controlled material removal in manual reaming tasks

JBO Thread Ring Gauge (NoGo) - Metric Coarse - Right Hand - 6h - M42 x 4.5 FHH Its left-hand spiral flute pairedThe JBO Thread Ring Gauge (NoGo) Metric Coarse, Right Hand, 6h, M42 x 4. 5 is a precision tool designed to verify external threads quickly and reliably. Made from hardened steel, it withstands daily wear in workshop environments while maintaining stable, repeatable measurements. Designed for quality control professionals, machinists, and maintenance teams, this NoGo gauge helps confirm that M42 x 4. 5 coarse threads meet the specified maximum