JBO Thread Ring Gauge (NoGo) - Metric Fine - Right Hand - 6g - M4 x 0.5 Face Mill Arbors - Through Coolant enabling fast tool changes and

enabling fast tool changes and reducing downtime

accurate hole finish with reduced chatter

it is built to BS 328/4 and holds ISO H5 tolerance for tight size control

Edge geometry: 180° cutting edge creates a true flat-bottom counterbore for uniform recess depths

ensure proper thread engagement

JBO Thread Ring Gauge (NoGo) - Metric Fine - Right Hand - 6g - M4 x 0.5 Face Mill Arbors - Through Coolant enabling fast tool changes andThe JBO Thread Ring Gauge (NoGo) is a precision tool for verifying external metric threads, specifically M4 x 0. 5, in a compact ring gauge format. Its ideal for engineers, machinists, quality inspectors, and assembly teams who need fast, reliable thread checks against standard specifications. Designed for tough shop environments, the gauge features hardened steel construction, right hand orientation, and metric fine tolerance (6g). This combination