Vermont Gage 361127020 Threaded Ring Gage 1/4-28 Unf 3A Go

Product Description

The VERMONT GAGE 361127020 is a Go-class threaded ring gage machined from tool steel for inspecting external threads to UNF standards. Sized for a 1/4-28 thread form, this single-ring gage is used to verify that a male-threaded part meets the minimum material condition required by Class 3A tolerance. A part that passes the Go gage confirms the thread pitch diameter and form are within the upper limit of the tolerance band. Manufactured to NIST-traceable standards, this gage is a standard piece of thread inspection tooling in machine shops, fabrication facilities, and quality-control environments.

This gage is suited for production inspection and incoming quality checks on fasteners, fittings, and machined components carrying a 1/4-28 UNF external thread. Class 3A represents a tight-tolerance fit class commonly specified in aerospace, hydraulic, and precision mechanical assemblies where thread fit and strength are critical. The single-ring design is the standard form for Go-ring gage applications in bench and floor inspection use.

Key Features

• Go-class ring gage for 1/4-28 UNF external thread inspection
• Class 3A tolerance classification for tight-fit precision thread verification
• Single-ring construction for dedicated Go-function use
• Tool steel construction for wear resistance and dimensional stability
• Manufactured to NIST-traceable standards for reliable measurement traceability

Compatibility

Designed for inspection of external 1/4-28 UNF Class 3A threads on male-threaded fasteners, fittings, and machined components.

Installation Notes

Threaded ring gages are handled and applied by quality control technicians and machinists, not field trades. Store gages in a clean, dry location and handle them without dropping to preserve calibration. Do not force the gage onto a thread; if the Go gage does not pass freely under hand pressure, the part is out of tolerance. Periodic recalibration against NIST-traceable masters is recommended to maintain measurement integrity.