Vermont Gage 361141020 Threaded Ring Gage 1/2-20 Unf

Product Description

The VERMONT GAGE 361141020 is a single-ring threaded ring gage used to verify the external thread form and pitch diameter of fasteners and threaded components. This is a Go-class gage, meaning it confirms that a threaded part meets the minimum acceptable thread geometry and will assemble properly with a mating component. Manufactured from tool steel to maintain dimensional stability under repeated use, it is sized for 1/2-20 UNF threads and rated to Class 3A tolerances. Machinists, quality control technicians, and toolroom personnel use this gage as part of go/no-go inspection routines on production or job-shop floors.

This gage is applied wherever 1/2-20 UNF external threads require dimensional verification to Class 3A tolerance standards. Class 3A represents a close-tolerance fit commonly specified for high-strength fastener applications in aerospace, automotive, and precision mechanical assemblies. The Go ring is threaded onto the workpiece by hand; a conforming part will accept the gage through the full thread length. It is suited for use at incoming inspection stations, in-process quality checks, and final acceptance testing.

Key Features

• Go designation confirms external thread pitch diameter meets Class 3A minimum tolerance
• 1/2-20 UNF thread size for fine-pitch unified national thread inspection
• Tool steel construction resists wear and maintains calibration over extended service
• Single-ring design for dedicated Go-function inspection
• Traceable to NIST standards for use in calibrated quality systems

Compatibility

Designed for inspection of external 1/2-20 UNF Class 3A threaded workpieces in accordance with unified inch screw thread standards.

Installation Notes

Threaded ring gages are handled and used by quality technicians and machinists; no power tools or utility shutoffs are required for gage use. Thread the Go ring onto the workpiece by hand only — do not force or use a wrench, as this can damage both the gage and the part being inspected. Store gages in a protective case away from abrasive materials and temperature extremes to preserve calibration. Periodic recertification against NIST-traceable masters is recommended to maintain measurement integrity in ISO or AS9100 quality environments.