Osg 1500100500 Plug Thread Gage 4-40 2B Double End

Product Description

The OSG 1500100500 is a double-end plug thread gage used to verify internal thread quality on 4-40 unified coarse fastener holes. 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 tolerance condition in a single tool. The gage is manufactured from high speed steel for wear resistance and dimensional stability. A handle is included. This tool is used by machinists, quality technicians, and inspectors working to 2B thread class tolerances in production or maintenance environments.

This gage is suited for inspection of 4-40 threaded holes in light mechanical assemblies, electronic enclosures, instrument panels, and precision machined components. The 2B classification reflects standard commercial and industrial internal thread tolerance requirements. Double-end configuration reduces tool changeover time during inspection runs. Typical users include CNC shops, assembly lines, and field maintenance teams requiring thread verification on small-diameter fastener locations.

Key Features

• Double-end design with Go and No Go members on a single gage body
• High speed steel construction for dimensional stability and long service life
• Covers 4-40 thread size to 2B tolerance class
• Handle included — no separate handle purchase required
• Compact overall length of 3 inches suits confined inspection areas

Compatibility

Designed for inspection of 4-40 class 2B internal threads in accordance with unified inch screw thread standards.

Installation Notes

Thread gages are inspection tools, not cutting tools — never force a plug gage into a threaded hole. The Go end should pass through the full length of the thread under hand pressure only; the No Go end should not enter more than two turns. Clean threads of chips and cutting fluid before gaging to avoid false readings. Handle and gage members should be stored clean and protected from impact to preserve calibration.