Spi 34-361-6 Plug Thread Gage 6-40 2B Double End

Product Description

The SPI 34-361-6 is a double-end plug thread gage designed to verify internal thread quality on 6-40 threaded holes. It checks both Go and No Go conditions in a single tool, confirming that a threaded feature accepts a conforming fastener and rejects an out-of-tolerance one. The gage is manufactured from steel and conforms to NIST standards, making it suitable for calibrated inspection environments. A handle is included. Licensed machinists, quality control inspectors, and precision fabricators use this type of gage as part of standard thread verification workflows in manufacturing and maintenance settings.

This gage is used wherever 6-40 internal threads require dimensional verification, including precision machined components, instrument enclosures, and small-fastener assemblies. The 2B classification designates a standard commercial tolerance class for inch-series unified threads, covering the majority of general-purpose internal thread applications. The double-end design places the Go member on one end and the No Go member on the other, eliminating the need for two separate gages on the same inspection station.

Key Features

• Verifies 6-40 internal threads to 2B tolerance class per NIST standards
• Double-end design with Go and No Go members on a single tool
• Steel construction for durability in production inspection environments
• NIST traceability certification included for calibrated measurement programs
• Handle included — no separate handle purchase required

Compatibility

Designed for inspection of 6-40 unified inch-series internal threads classified to 2B tolerance, as found in general-purpose threaded components across manufacturing and assembly applications.

Installation Notes

Plug thread gages are used by quality control technicians and precision machinists — no power tools or utilities need to be shut down before use. Thread the Go end into the inspected hole using hand pressure only; forced insertion can damage the gage and produce false readings. Store gages in a protective case away from contaminants and other metal tooling to preserve calibration. Re-certification intervals should follow your facility's calibration management program.