Spi 29-287-0 Class Zz Plus Plug Gage 0.287 in

Product Description

The SPI 29-287-0 is a Class ZZ Plus plug gage designed to verify the diameter of drilled, reamed, or bored holes to a nominal size of 0.287 inches. Built from steel, it delivers a stated tolerance of 0.0002 inches, making it suitable for production inspection and quality control tasks where accurate go/no-go verification is required. Machinists, tool-and-die workers, and quality technicians use plug gages like this to confirm that a finished bore meets its print specification without the need for an indicating instrument.

This gage is used in machine shops, manufacturing facilities, and production inspection environments where hole diameter must be verified to tight tolerances. It is appropriate for checking holes in metal workpieces such as fixtures, housings, and precision-machined components. The 0.287-inch nominal size covers a common bore range found in general metalworking and production applications. Class ZZ Plus designates the tolerance class, indicating a level of accuracy suited to general-purpose inspection rather than master or working-gage-level precision.

Key Features

• Nominal measurement diameter of 0.287 inches for direct hole verification
• Class ZZ Plus tolerance class at 0.0002 inches for reliable go/no-go inspection
• Steel construction for durability in production shop environments
• Compact and lightweight at 0.2 pounds for easy handling at the inspection point
• Single-piece package quantity supports individual bench or inline use

Compatibility

Designed as an OEM-style plug gage for use in general-purpose hole inspection applications requiring a 0.287-inch nominal bore diameter at Class ZZ Plus tolerance.

Installation Notes

Plug gages are used by quality technicians and machinists and require no permanent installation. Clean the gage and the bore before each use to prevent debris from affecting the measurement result. Handle steel gages with care to avoid nicks or corrosion that could compromise tolerance accuracy. Store the gage in a protective case away from moisture when not in use.