Spi 34-341-8 Plug Thread Gage 1-72 2B Double End Go No Go

Product Description

The SPI 34-341-8 is a double-end plug thread gage designed to verify internal threads to the 1-72 UNF specification at a 2B tolerance class. One end serves as the Go member and the other as 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 handle included and comes with a traceability certification traceable to NIST standards. Machinists, quality inspectors, and tool-room technicians use this gage on the shop floor or in the inspection lab to quickly accept or reject tapped holes without additional setup.

This gage is suited for inspecting fine-pitch internal threads in precision components where 1-72 UNF threading is specified. Typical applications include aerospace hardware, instrument assemblies, and small-fastener tapped holes where thread fit and tolerance must be verified to a documented standard. The double-end configuration eliminates the need to handle two separate gages during a single inspection operation, reducing cycle time on the inspection bench.

Key Features

• Double-end design combines Go and No Go members in one tool for efficient thread verification
• Covers 1-72 UNF thread size at 2B tolerance class
• Handle included — no separate handle purchase required
• NIST-traceable certification included for documentation and quality-system compliance
• Steel construction for durability in production and inspection environments

Compatibility

Designed for inspection of internal 1-72 UNF 2B class tapped holes in any material where that thread form and tolerance class are specified.

Installation Notes

Thread gages are inspection tools, not cutting tools — do not force the Go member into a hole or use power tools to drive the gage. Apply the Go end by hand with light, steady axial pressure; a properly tapped hole should accept the Go end and reject the No Go end. Keep gages clean and lightly oiled when stored to prevent corrosion on the steel surfaces. Gages should be periodically re-certified to maintain traceability documentation in compliance with your quality management system.