Features: 1. Durable High Hardness Metal: The nut bolt thread checker is made from high hardness metal, ensuring durability and practicality for all your thread checking needs. 2. Easy and Accurate Identification: 3. Dual End Design: Each size of the bolt 44 male/female gauges features a male gauge on one end and a female gauge on the other, providing comprehensive measurement capabilities. 4. Inch and Metric Sizes: The inch metric bolt nut screw thread checker includes 14 common inch sizes marked in silver and 12 common metric sizes marked in black, ensuring you have the right tool for any job. 5. Convenient and Portable: All 44 male/female gauges inspection measuring tools are strung together with a hanging ring, making it extremely convenient to carry and use wherever you need it. Specification: Origin: Mainland China DIY Supplies: Metalworking Metric system: M4*0.7, M5*0.8, M6*1, M7*1, M8*1, M8*1.25, M10*1, M10*1.25, M10*1.5, M12*1.25, M12*1.5, M12*1.75 Imperial: 6-32,8-32,10-24,10-32,1/4-20,1/4-28,5/16-18,5/16-24,3/8-16,3/8-24,7/16-14,7/16-20,1/2-13,1/2-20 Material: 45 steel Surface treatment: electroplating Product packaging size: about 180.00x145.00x15.00mm/7.09x5.71x0.59inch