Spi 29-591-5 Class Zz Plus Plug Gage 0.591 in

Product Description

The SPI 29-591-5 is a Class ZZ Plus plug gage used to verify the dimensional accuracy of drilled, reamed, or bored holes. It measures a nominal diameter of 0.591 inches with a tolerance of 0.0002 inches, making it suitable for go/no-go inspection work in production and quality control environments. Constructed from steel, this gage provides the durability needed for repeated use in shop-floor measurement applications. Machinists, toolmakers, and quality technicians rely on plug gages like this one to confirm that inside diameters conform to print specifications before parts move to the next stage of manufacturing.

This gage is intended for use in precision measurement and inspection of cylindrical bores. It is well suited for incoming inspection, in-process quality checks, and final part verification in machine shops, manufacturing facilities, and job shops. The Class ZZ Plus designation indicates the tolerance class of the gage itself, which determines how closely the gage conforms to its stated nominal size. This makes it appropriate for general-purpose inspection where a high degree of gage accuracy is required without the cost of tighter-class toolroom gages.

Key Features

• Nominal measurement diameter of 0.591 inches for precise bore verification
• Tolerance of 0.0002 inches meets Class ZZ Plus gage accuracy standards
• Steel construction provides wear resistance for repeated shop use
• Compact and lightweight at 0.2 pounds for easy handling during inspection
• Single-piece packaging suitable for individual workstation or toolbox use

Compatibility

Designed as a general-purpose plug gage for inspecting cylindrical bores with a nominal diameter of 0.591 inches in standard machining and quality inspection applications.

Installation Notes

Plug gages are handled and used by machinists, toolmakers, and quality control inspectors — no installation in the mechanical sense is required. Store the gage in a protective case away from other tooling to prevent surface damage. Clean the gage and the bore being measured before use to avoid false readings caused by chips or debris. Do not force the gage into an undersize bore, as this can damage the gage surface and compromise measurement accuracy.