Spi 34-414-3 Plug Thread Gage 5/8-18 3B Double End

Product Description

The SPI 34-414-3 is a double-end plug thread gage designed to inspect and verify 5/8-18 inch internal threads to 3B class tolerance. The Go end confirms the thread falls within the minimum material condition, while the No Go end verifies it does not exceed the maximum material condition. This gage is used in precision machining, manufacturing, and inspection environments where thread conformance to NIST-traceable standards is required. A handle is included. Installation and use require no special tooling beyond the gage itself and standard inspection procedures.

This plug thread gage is suited for production floor and quality control inspection of 5/8-18 unified national thread forms classified at 3B tolerance. The double-end design allows the technician or inspector to complete both Go and No Go checks without switching tools, reducing inspection time on threaded bores in metal components. Traceability documentation is included with each unit, supporting compliance with quality management systems that require NIST-referenced calibration records.

Key Features

• Double-end design provides both Go and No Go checks in a single tool
• Calibrated to 5/8-18 thread size at 3B class tolerance
• NIST traceability certification included with each unit
• Steel construction for durability in production and inspection environments
• Handle size 3 included — no additional handle purchase required
• Conforms to NIST standards for thread gage inspection

Compatibility

Designed for inspection of internal 5/8-18 unified national threads classified to 3B tolerance in metal components and assemblies.

Installation Notes

Thread gages should be handled and stored carefully to prevent damage to the gage members. Apply thread gage oil or light lubricant before use to protect the gage and reduce wear. Inspect the gage itself periodically for wear and recalibrate or replace as required by your quality management procedures. Only qualified inspectors or machinists should use precision thread gages to ensure accurate results.