Spi 23-139-9 Threaded Ring Gage Class 2A Go No Go

Product Description

The SPI 23-139-9 is a double-ring threaded ring gage designed for inspecting external threads to Class 2A tolerance standards. It includes both a Go and a No Go ring in a single unit, allowing technicians to verify that a threaded workpiece falls within the acceptable tolerance band in one setup. Manufactured from tool steel for wear resistance, and conforming to NIST standards, this gage is used for quality control and inspection tasks in machining, manufacturing, and assembly environments. It weighs 0.118 pounds and measures 1 inch in width and 0.27 inches in length, making it a compact bench or floor inspection tool.

This gage is suited for production inspection and incoming quality control wherever Class 2A external thread tolerances must be verified. Machinists, quality technicians, and precision measurement professionals use this type of gage to confirm that threaded fasteners, fittings, or machined parts meet specification before assembly. The double-ring design reduces handling time by combining Go and No Go checks into a single instrument, which is particularly useful in high-throughput inspection settings.

Key Features

• Go and No Go rings combined in a single double-ring gage for efficient thread inspection
• Class 2A classification for inspecting standard commercial external thread tolerances
• Tool steel construction provides durability and resistance to wear in production environments
• Conforms to NIST standards for traceable measurement accuracy
• Compact form factor at 0.27 inches in length and 1 inch in width for easy bench use

Compatibility

Designed as an OEM-style replacement and standard inspection tool for Class 2A externally threaded components in machining and manufacturing applications.

Installation Notes

Thread ring gages are inspection instruments and do not require installation in the traditional sense. Qualified quality technicians or machinists should handle and store the gage according to standard metrology practices to preserve calibration and surface integrity. Always clean threads and the gage surfaces before inspection to prevent false readings. Periodic re-calibration against NIST-traceable standards is recommended to maintain measurement integrity.