Spi 34-294-9 Plug Thread Gage 1/2-28 6H No Go

Product Description

The SPI 34-294-9 is a single-end No Go plug thread gage used to verify internal thread quality on 1/2-28 threaded holes to the 6H tolerance class. When a No Go gage enters the thread beyond two turns, the thread is out of tolerance and the part fails inspection. Machined from steel for durability and dimensional stability, this gage conforms to ANSI standards and ships with a NIST traceability certification. A size 2 handle is required for use but is sold separately. This tool is used by machinists, quality technicians, and precision manufacturing inspectors on production and receiving inspection lines.

The 34-294-9 is suited for inspection of 1/2-28 internal threads in aerospace, automotive, firearms, and general precision manufacturing applications. The 6H tolerance class is a standard fit used widely in metric-style unified thread inspection. This gage is appropriate for both incoming inspection of threaded components and in-process quality checks on CNC-machined parts. It is typically used alongside a matching Go gage to complete a full pass-fail thread verification.

Key Features

• No Go member only — confirms upper thread tolerance limit for 1/2-28 6H threads
• Steel construction for long-term dimensional stability under repeated use
• NIST traceability certification included for calibration documentation requirements
• Conforms to ANSI thread gage standards
• Single-end design — size 2 handle required, sold separately

Compatibility

Designed for inspection of 1/2-28 internal threads to the 6H tolerance class per ANSI standards. Compatible with standard size 2 thread gage handles sold separately.

Installation Notes

Thread gages are precision inspection tools and should be handled carefully to avoid dropping or contact with abrasive surfaces. Store in a protective case when not in use to preserve calibration. Apply a light thread gage lubricant before use to reduce wear and protect the gage member. Periodic recalibration against a certified master is recommended to maintain traceability to NIST standards.