Spi 23-203-3 Threaded Ring Gage 7/8-20 Class 2A Go No Go

Product Description

The SPI 23-203-3 is a double-ring threaded ring gage designed to verify external thread conformance on 7/8-20 UNF fasteners and threaded components. It includes both a Go ring and a No Go ring in a single double-ring configuration, allowing technicians to confirm that threads fall within acceptable tolerance limits for Class 2A fit. Manufactured from tool steel, the gage is built to withstand repeated use in production and inspection environments. NIST traceability certification is included, supporting documentation requirements for quality management systems. The part weighs 2.165 pounds and measures approximately 2.63 inches in width and 0.7 inches in length.

This gage is used in machine shops, manufacturing facilities, maintenance departments, and quality control labs wherever 7/8-20 Class 2A external threads must be inspected before assembly or shipment. It is appropriate for incoming inspection of threaded fasteners, in-process verification during machining operations, and final inspection of threaded shafts, bolts, and fittings. The double-ring design keeps both Go and No Go gages together in a single unit, reducing the chance of a missing component during inspection routines.

Key Features

• Go and No Go rings in a single double-ring body for complete Class 2A thread verification
• Thread size 7/8-20 UNF for external thread inspection
• Class 2A tolerance classification for standard commercial and industrial fastener applications
• Tool steel construction for durability under regular production and inspection use
• NIST traceability certification included for quality system documentation

Compatibility

Designed for inspection of external threads conforming to 7/8-20 UNF Class 2A specifications. Suitable for use with threaded shafts, bolts, fittings, and any component where 7/8-20 external thread conformance must be verified.

Installation Notes

Threaded ring gages are handled and used by machinists, quality control inspectors, and metrologists. Store the gage in its case when not in use to protect the thread form from damage and corrosion. Apply a light coat of clean machine oil before storage to prevent rust on the tool steel surfaces. Do not force the gage onto threads; resistance or binding on the Go ring indicates a nonconforming part and the gage should never be used to chase or reform threads.