Precision Sizing: Our nut and bolt thread checker is meticulously crafted from CNC-machined to adhere to the Go & No-Go Class 2B ANSI Standard, ensuring accurate sizing for both internal and external threads. Say goodbye to second-guessing and mismatched hardware - embrace flawless accuracy effortlessly. | 30 Nut and Bolt Thread Sizes: Our nut and bolt thread checker instantly identifies 30 distinct sizes, covering Metric thread sizes from M3 x 0.5 to M14 x 2.0, and Imperial threads from #4 - 40 Coarse to 1/2 - 20 Fine. Each size comes with both a male thread (for nuts and washers) and a female thread (for bolts and screws), ensuring compatibility with all your standard hardware! | Easy to Use: Our bolt and nut identifier gauge simply matches your nuts and bolts to the corresponding slots to identify the size and pitch accurately. The intuitive design and easy-to-read laser-etched markings make using our thread checker a breeze, even for beginners. | Multi-Functional Design: Our screw thread gauge is crafted from 6061 aluminum with a sleek anodized finish, ensuring durability and resilience. Convenient 15CM and 6-inch rulers on both sides. It's a tool designed for lasting reliability and convenience. | Versatile Mounting Options: Featuring a convenient hanging hole and four anti-slip silicon feet, our thread checker offers versatile mounting options. Hang it on your workshop wall for easy access, or let it sit securely on any surface as you work - the choice is yours!