Norm Accuracy: Complies with ASTM B89.1 criteria, suitable for standard control, automobile repair, and heavy equipment maintenance, ensuring accurate thread measurement Permanent Spaceflight Grade Substancemail: Produced from excellent metal with light incised indicators for permanent clearness, ensuring excellent wear resistance and oxidation resistance in tough conditions Wide and Metric Coveragemail: Features 28 and 24 metric thread gauges with color ciphered pulls for rapid identification, even in shadowy conditions, enhancing efficiency Comprehensive Thread Identificatparticlemail: This 52 piece set includes both and STANDARD thread gauges, covering measurements from 2 56 to 1 12 and M20 (metric), making it ideal for workshops, maintenance, and gear inspection Transportable and User Friendly Planumberebog: Detachable thread gauges allow easy use in tight spaces, and brief set accommodates into tool smock pouches for on proceed inspections, Manufacturer: YUNGLOO