- Accurate thread pitch measurement: This thread checker measures both internal and external thread pitch with precision in standard and metric. It includes 51 or 52 pieces, depending on the model, to accurately check a wide range of threads in imperial and metric systems, from 0.25 mm to 6.00 mm. - Magnetic head for easy use: The magnetic head attaches to metal surfaces, preventing slippage and ensuring stable readings. This makes it ideal for workshops or industrial settings where mobility and reliability matter. - Adjustable rotary switch for flexibility: The rotary switch allows easy adjustment to quickly switch between different thread sizes. Whether you are measuring fine or coarse threads, the adjustable feature enables accurate readings with less effort. - Strong and long-lasting construction: Made from stainless steel and hardened through quenching, this thread gauge set offers strong performance and durability for long-term use in any environment. Use scenarios - In a machine shop, quickly verify bolt and nut compatibility when assembling components that require both imperial and metric threads. - During equipment maintenance, check internal threads in housings or blocks to confirm fit before final assembly. - On a production line, confirm thread pitch before part installation to prevent mismatches and rework.