The JBO Thread Plug Gauge (NoGo) – Metric Coarse, Left Hand, 6H, M45 x 4.5 – is a precision inspection tool designed to quickly verify the size of internal threaded holes. Built for quality control, machining, assembly, and maintenance teams, it helps ensure threaded connections will meet spec and function reliably in real-world applications.

Crafted from hardened steel for durability and long life, this NoGo gauge is built to withstand daily shop conditions. The left-hand thread configuration and exact M45 x 4.5 dimensions provide a dependable reference for verifying hole size, so you can trust your assemblies from first run to final production.

• Exact NoGo for M45 x 4.5 metric coarse threads: quickly confirms holes do not exceed maximum size, helping prevent mismatches and costly rework.
• Left-Hand thread compatibility: specifically designed to inspect left-handed threaded holes, reducing read errors and ensuring correct fits.
• Rugged, ergonomic construction: hardened steel body with a knurled grip delivers durable, repeatable readings and comfortable handling—even with gloves.

This gauge streamlines quality checks by delivering fast, repeatable measurements that improve workflow and reduce downtime. Its robust design supports consistent performance across inspections, giving you confidence in every threaded connection and helping you meet tight tolerances with less guesswork.