The JBO Thread Plug Gauge is a precision inspection tool built to verify UNJF (Unified Fine) threads in left-hand holes. It’s ideal for manufacturers, automotive shops, aerospace assemblies, and precision workshops that rely on quick, reliable go/no-go checks for 3/8 x 24 threads in class 3B. With its compact, dual-ended design, you can test both the minimum and maximum limits with one instrument, keeping your workflow efficient.

This gauge is designed for heavy use in demanding environments. It features a knurled, textured sleeve for a secure grip and durable metal ends machined to tight tolerances. The left-hand configuration and UNJF Go-No/Go specification ensure compatibility with your threaded components and deliver consistent results across inspections.

• Dual-ended Go/No-Go design: Quickly verify that threads meet the required limits with one tool, reducing inspection time and eliminating guesswork.
• Left-hand UNJF 3B 3/8 x 24 compatibility: Precisely engineered to the UNJF standard for left-hand threads, providing reliable pass/fail decisions every check.
• Rugged, knurled construction: Built for durability in busy environments, with a textured grip and corrosion-resistant finish that stands up to daily use.

This plug gauge helps streamline quality control by delivering clear, repeatable results that support accurate assembly and reduced downtime. With its focused, user-friendly design, you’ll gain confidence in every measurement, improve workflow efficiency, and maintain consistent threading checks across your production line.