Spi 29-371-2 Class Zz Plus Plug Gage 0.371 in

Product Description

The SPI 29-371-2 is a Class ZZ Plus plug gage used to verify the diameter of machined holes to a high degree of accuracy. Manufactured from steel, this go/no-go style gage checks that a bored or reamed hole falls within the specified tolerance band. It measures a nominal diameter of 0.371 inches with a tolerance of 0.0002 inches, making it suited for precision inspection work on production floors and in machine shops. Machinists, toolmakers, and quality control technicians use plug gages as a fast, repeatable method to confirm hole size without the need for a calibrated bore gauge readout.

This gage is appropriate for inspection of close-tolerance holes in metal components across general manufacturing, tooling, and mechanical assembly applications. The 0.371-inch nominal size targets holes commonly encountered in shaft-fit and fastener-clearance inspection scenarios. It is used in both job-shop and production environments where fast pass/fail verification of hole diameter is required. Sold as a single gage unit.

Key Features

• Nominal measurement diameter of 0.371 inches for precise hole inspection
• Class ZZ Plus tolerance rating of 0.0002 inches for accurate pass/fail gauging
• Steel construction for durability and dimensional stability
• Compact and lightweight at 0.2 pounds for easy handling at the workstation
• Single-piece unit ready for immediate use in inspection routines

Compatibility

Designed as a standard Class ZZ Plus plug gage for use in hole diameter inspection of steel, aluminum, and similar machined components where a 0.371-inch nominal bore diameter must be verified.

Installation Notes

Plug gages are handled and used by machinists and quality control technicians rather than installed in a system. Before use, clean the gage and the hole being checked to remove chips, coolant, and debris that could affect the reading. Never force a plug gage into a hole; forced insertion can damage the gage or the workpiece and will produce unreliable results. Store the gage in a protective case away from other tools to prevent nicks or wear that would affect calibration.