Spi 34-293-1 Plug Thread Gage 1/2-28 6H Single End No Go

Product Description

The SPI 34-293-1 is a single-end No Go plug thread gage used to inspect 1/2-28 threaded holes to the 6H tolerance class. The gage checks that an internal thread has not been cut beyond the maximum material condition, which would cause an unacceptable fit. Manufactured from steel, the 34-293-1 ships with a traceability certification traceable to NIST, meeting ANSI standards. A Size 2 handle is required for use but is sold separately. This type of precision gage is a standard inspection tool in machining, assembly, and quality-control environments across industrial and trade applications.

The 34-293-1 is suited for use wherever 1/2-28 internal threads must be verified during production or incoming inspection. The 1/2-28 thread size is common in firearms, precision instrumentation, and specialty fastener applications. Machinists, quality technicians, and assembly personnel use No Go gages as part of a two-gage GO/NO GO system to ensure threaded features fall within specified tolerance limits. The included NIST-traceable certification supports quality documentation requirements in regulated manufacturing environments.

Key Features

• No Go member of a GO/NO GO plug gage set for 1/2-28 internal threads
• 6H tolerance class per ANSI standards
• NIST-traceable certification included for quality and audit documentation
• Steel construction for durability and wear resistance in production use
• Single-end configuration — one gage member per piece
• Requires a Size 2 handle, sold separately

Compatibility

Designed for inspection of 1/2-28 class 6H internal threads per ANSI standards. Pair with a matching GO plug gage to complete a full GO/NO GO thread inspection system.

Installation Notes

Thread gages are precision inspection instruments and should be handled and stored accordingly. A Size 2 gage handle must be installed before use — do not attempt to turn the gage member by hand in a way that could damage threads or alter the gage. Gages should be cleaned and lightly oiled before and after each use to prevent corrosion. Periodically verify the gage against its NIST-traceable certificate and re-calibrate per your facility quality-management program.