Spi 34-371-5 Plug Thread Gage 12-24 2B Double End

Product Description

The SPI 34-371-5 is a double-end plug thread gage designed to verify internal thread conformance on 12-24 threaded holes. One end carries the Go member; the opposite end carries the No Go member. When the Go end passes and the No Go end does not, the thread is confirmed within 2B class tolerance limits. The gage is manufactured from steel for dimensional stability under repeated use. A handle is included. NIST traceability certification ships with the unit, supporting quality-system documentation requirements in production and inspection environments. Machinists, quality technicians, and precision tool trades use this type of gage in thread inspection on machined components, fastener holes, and tapped assemblies.

The 34-371-5 is suited to inspection of 12-24 unified national coarse internal threads in manufacturing, job shop, and maintenance-repair-operations environments. The 2B classification covers the standard tolerance class used in the majority of general-purpose fastener applications. The double-end design consolidates Go and No Go inspection into a single tool, reducing changeout time on the inspection bench or shop floor. The included handle is sized for the gage and ready to use without additional tooling.

Key Features

• Double-end design: Go member on one end, No Go member on the other end in a single tool
• Inspects 12-24 unified national coarse internal threads to 2B class tolerance
• Steel construction for dimensional stability and wear resistance
• NIST traceability certification included for quality-system compliance
• Handle included — no separate purchase required

Compatibility

Designed for inspection of 12-24 internal threads conforming to 2B class tolerance limits per NIST standards. Verify thread specification and tolerance class requirements before use.

Installation Notes

Thread gages are inspection instruments, not cutting tools — do not apply torque beyond hand pressure when gauging. Clean threads of chips, oil, and debris before inspection to avoid false readings or gage wear. Store the gage in its case when not in use to protect the precision ground members. Periodic re-calibration against NIST-traceable masters is recommended to maintain measurement integrity.