Spi 37-164-1 Plug Thread Gage M20x2.5 6H Single End No Go

Product Description

The SPI 37-164-1 is a single-end plug thread gage designed to inspect M20x2.5 internal threads to the 6H tolerance class. It is configured as a No Go member, used to verify that a tapped hole has not been cut oversize or out of tolerance. When a properly tapped hole rejects this gage, the thread is confirmed within the upper limit of the 6H tolerance band. Machinists, quality inspectors, and precision tool trades use this gage in production and inspection environments where metric thread conformance is required. Handle is not included and must be sourced separately.

This gage applies to metric threaded components requiring M20x2.5 thread verification in accordance with 6H classification standards. It is suited for use in manufacturing, machining, and assembly inspection applications where internal thread quality must be confirmed before parts advance in production. The single-end configuration keeps the gage compact and straightforward to use in benchtop or floor-level inspection setups.

Key Features

• No Go member confirms internal thread is within the upper 6H tolerance limit
• M20x2.5 thread size covers a widely used metric fastener pitch in mechanical assemblies
• 6H classification meets standard tolerance requirements for general-purpose metric threaded holes
• Single-end design provides a compact, dedicated No Go inspection tool
• ANSI traceability certification included for quality documentation and audit compliance
• Calibrated to NIST-traceable standards for accuracy confidence in precision inspection

Compatibility

Designed for use with standard plug gage handles accepting the appropriate shank size. Handle is not included with this gage. Suitable for inspecting any M20x2.5 internally tapped hole held to the 6H tolerance class.

Installation Notes

Thread gages are inspection tools, not cutting tools. Always ensure the tapped hole is clean and free of chips, coolant, or debris before gauging. Apply the No Go member by hand without forcing rotation. If the gage enters the hole, the thread is out of tolerance and the part should be rejected or reworked. Store the gage in its protective case when not in use to prevent wear to the precision ground threads.