Spi 34-405-1 Plug Thread Gage 9/16-12 2B Double End

Product Description

The SPI 34-405-1 is a double-end plug thread gage designed to verify 9/16-12 UNC internal threads to the 2B tolerance class. One end carries the Go member and the other carries the No Go member, allowing a technician to confirm both the minimum and maximum thread acceptance limits in a single tool. The gage ships with a size 3 handle and includes a traceable calibration certificate referenced to NIST standards. Machinists, quality control inspectors, and precision maintenance technicians use this type of gage to validate threaded holes in manufactured parts, fixtures, and field-machined components.

This gage is suited for production floor inspection, incoming material verification, and field QC work wherever 9/16-12 UNC threaded holes must meet 2B class tolerances. The double-end configuration keeps both Go and No Go members on one handle, reducing tool changeover time during repetitive inspection runs. The included NIST-traceable certification supports documented quality programs, ISO shop requirements, and audit-ready inspection records.

Key Features

• Go and No Go members on a single double-end handle for complete 2B acceptance checks
• Calibrated to NIST standards with traceability certification included
• Size 3 handle included — no separate handle purchase required
• Steel construction for durability in production and field inspection environments
• Verifies 9/16-12 UNC threads to 2B tolerance class

Compatibility

Designed for inspection of 9/16-12 UNC internal threads conforming to 2B tolerance class specifications. Fits standard size 3 plug gage handles.

Installation Notes

Plug thread gages are used by machinists and quality inspectors — no power source or lockout is required. Handle the gage members carefully to avoid nicks or burrs that would affect measurement accuracy. Store the gage in a protective case away from other metal tools. Periodic re-calibration against a NIST-traceable master is recommended to maintain certification validity.