Vermont Gage 361110040 Threaded Ring Gage 4-40 Unc

Product Description

The VERMONT GAGE 361110040 is a single-ring threaded ring gage used to verify the maximum material condition of external threads. Classified as a No Go gage to Class 3A tolerances, it checks that a 4-40 UNC male thread does not exceed its allowable pitch diameter limit. When a properly cut thread refuses entry to the No Go ring, the thread is within tolerance. Manufactured from tool steel and traceable to NIST standards, this gage is a standard inspection tool in precision machining, assembly, and quality control environments. It is used by machinists, inspectors, and field technicians who require reliable thread verification.

This gage is intended for inspection of 4-40 UNC threaded fasteners, bolts, screws, and threaded components in precision manufacturing and assembly operations. Class 3A designates a tight-tolerance fit commonly required in aerospace, electronics, instrumentation, and other applications where thread fit and load-bearing integrity are critical. The single-ring design handles the No Go function only, and is typically used alongside a separate Go ring gage to complete a full pass-fail thread inspection.

Key Features

• No Go classification confirms external threads do not exceed maximum pitch diameter for Class 3A tolerance
• 4-40 UNC thread form for inspection of fine-pitch, small-diameter fasteners
• Tool steel construction provides wear resistance for repeated inspection use
• NIST-traceable standards compliance supports quality assurance documentation
• Single-ring format dedicated to No Go function for straightforward pass-fail inspection

Compatibility

Designed for inspection of external 4-40 UNC threads manufactured to Class 3A tolerance specifications.

Installation Notes

Thread ring gages are inspection instruments and do not require installation. Handle with clean, dry hands or lint-free gloves to prevent corrosion from skin contact. Store in a protective case away from chips, coolant, and abrasive surfaces when not in use. Periodic calibration against NIST-traceable masters is recommended to maintain gage accuracy over time.