JBO Thread Ring Gauge (GO) - Metric Fine - Left Hand - 6g - M12 x 0.5 ER Mini Collet Chucks 42 mm hole sizing for

42 mm hole sizing for metalworking projects

with an uncoated surface to reduce friction

reducing tool deflection during deep groove profiling

or coating that fits your specific project without compromising quality

accurate contours on narrow ribs—perfect for engineers

JBO Thread Ring Gauge (GO) - Metric Fine - Left Hand - 6g - M12 x 0.5 ER Mini Collet Chucks 42 mm hole sizing forThe JBO Thread Ring Gauge (GO) Metric Fine, Left Hand, M12 x 0. 5 is a precision inspection tool designed to verify external thread diameters with accuracy and speed. Its ideal for engineers, machinists, quality professionals, and assembly teams who need reliable go no go checks to confirm parts meet exact size and fit requirements. Manufactured from hardened steel, this GO gauge provides lasting durability and wear resistance for busy shop floors and