Vermont Gage 361141030 Threaded Ring Gage 1/2-20 Unf

Product Description

The VERMONT GAGE 361141030 is a single-ring threaded ring gage used to verify external thread conformance on 1/2-20 UNF fasteners and threaded components. This is the No Go member of the Class 2A gage set, meaning it confirms that a threaded workpiece does not exceed the maximum material condition for that tolerance class. Manufactured from tool steel and traceable to NIST standards, the 361141030 delivers consistent, reliable rejection of out-of-tolerance parts on the shop floor, inspection bench, or in the field. Machinists, quality technicians, and tool-room professionals use this gage as part of go/no-go verification routines on production and maintenance work.

This gage applies wherever 1/2-20 UNF external threads must meet Class 2A fit requirements. Class 2A is the standard tolerance class for general-purpose inch fasteners, covering the majority of bolts, studs, and threaded shafts used in industrial, mechanical, and HVAC equipment assemblies. The No Go ring is used in conjunction with a matching Go ring to bracket acceptable thread tolerance. Use this gage for incoming inspection, in-process checks, or final verification of threaded parts.

Key Features

• No Go member for Class 2A UNF thread verification — rejects oversize threads that exceed maximum material limits
• 1/2-20 UNF thread form for general-purpose inch-series fastener inspection
• Single-ring design for straightforward hand-gage operation
• Tool steel construction for wear resistance in production inspection environments
• NIST-traceable standards compliance for use in documented quality systems

Compatibility

Designed for inspection of external 1/2-20 UNF Class 2A threaded workpieces in accordance with NIST-referenced thread standards. Use with a matching Class 2A Go ring gage to complete the go/no-go inspection pair.

Installation Notes

Threaded ring gages are hand tools used by quality technicians and machinists — no power equipment or utilities need to be shut down for routine gage use. Store gages in a clean, dry environment and handle with care to avoid dropping, which can damage the thread form and invalidate calibration. Periodically clean threads and check for wear, and recalibrate or replace the gage according to your quality system's gage R and R schedule. Do not force the No Go ring onto a borderline part; if the gage does not enter under hand pressure, the thread has failed inspection as intended.