Spi 34-356-6 Plug Thread Gage 5-40 3B Double End Go No Go

Product Description

The SPI 34-356-6 is a double-end plug thread gage used to inspect 5-40 UNC threaded holes to Class 3B tolerance. One end carries the Go member and the opposite end carries the No Go member, allowing a technician to verify both the minimum and maximum thread tolerance in a single tool. The gage is manufactured from steel for wear resistance and dimensional stability. A handle is included. NIST traceability certification ships with the gage, supporting quality-system documentation requirements in shop, manufacturing, and inspection environments. Machinists, quality technicians, and tool-room professionals use this gage as part of in-process or final inspection of threaded components.

The 34-356-6 is suited for inspecting 5-40 threaded holes in precision assemblies, electronics hardware, instrument panels, and light mechanical components where Class 3B fit is specified. The Go end confirms the thread will accept a mating fastener; the No Go end confirms the thread has not been cut oversized. The NIST traceable certification makes this gage appropriate for AS9100, ISO 9001, and similar quality programs that require documented measurement traceability.

Key Features

• Double-end design combines Go and No Go members in one handle for efficient thread inspection
• Inspects 5-40 UNC threads to Class 3B tolerance
• Steel construction for dimensional stability and extended service life
• NIST traceability certification included for quality-system compliance
• Handle included — no separate purchase required

Compatibility

Designed for inspection of 5-40 UNC threaded holes manufactured to Class 3B tolerance specifications.

Installation Notes

Thread gages are inspection tools, not cutting tools — never force the Go end into a thread or apply torque beyond hand pressure. The No Go end should not enter more than two turns; entry beyond that indicates an out-of-tolerance condition. Store the gage in its case and keep it clean and lightly oiled to preserve calibration. Re-calibration intervals should follow your facility quality plan and applicable gage standards such as ASME B47.1.