Name: Tooth gauge, thread gauge, thread ring gauge Model: M1-M160 (non-standard size gauge can be customized, please contact us if you need it.) Material: Gcr15 (GCr15 refers to a kind of high carbon chromium bearing steel with less alloy content, after quenching and low-temperature tempering, it has higher hardness, uniform structure, good wear resistance, and high contact fatigue performance) Accuracy: ring gauge 6g or 6h (default delivery is the general standard 6g; in addition, other accuracy gauges can be customized, please contact us if you need to) Unit: 1 pair ( T-GO and Z-No Go each) Thread Ring and Thread Setting Plug Gages are manufactured to inspect the Pitch Diameter and the Functional Thread. Thread gages are used to ensure the assembly of mating parts. T Go ; Z NO-GO