Clear Size Markings: Each tool features size engravings for quick identification, eliminating the hassle of searching for different specifications and speeding up inspection processes Wide Application Ranges: Suitable for professional and hobbyists in automotive repair, machinery maintenance, electrical installations, and home DIYer tasks, solving thread verification needs across multiple scenarios Premium Stainless Steel: Made from stainless steel for excellent resistance and durability, outperforming traditional steel by 3 times in harsh or humid industrial environments Complete Thread Checking set: This 44 piece set includes various nut and bolt thread checkers covering multiple specifications, ideal for mechanical repairs, assembly work, and DIYer projects to ensures proper thread matching and Portable Storage Case: Comes with a sturdy carrying case to keep all tools organized and protected during transport, perfect for workshops, factories, and on site repairs, Manufacturer: CAZSTYK