Spi 19-972-9 Class Zz Minus Plug Pin Gage 0.972 in

Product Description

The SPI 19-972-9 is a Class ZZ minus plug pin gage with a nominal measurement diameter of 0.972 inches and a tolerance of 0.0002 inches. Plug pin gages in the Class ZZ designation are go/no-go precision measurement tools used to verify hole diameter, bore size, and dimensional conformance in manufactured parts. This gage is machined from steel for durability and dimensional stability. Machinists, quality control technicians, and metrology lab personnel use plug gages as a fast, reliable method to confirm that drilled or bored holes meet print tolerances without requiring a CMM or inside micrometer setup.

This gage is suited for inspection of machined components in manufacturing, tool-and-die, automotive, aerospace, and general fabrication environments. The 0.972-inch diameter range covers a common bore size in mechanical assemblies. Class ZZ is a working-gage class appropriate for production floor inspection rather than master-gage calibration standards. The minus designation indicates the gage is manufactured to the minus side of the tolerance band, which is standard practice for go-type plug gages used to check minimum hole size acceptance.

Key Features

• Class ZZ tolerance class — suitable for production floor go/no-go inspection
• Minus tolerance designation — manufactured to the lower side of the tolerance band for correct go-gage function
• 0.0002-inch (0.0002 mm) tolerance for reliable dimensional verification
• Steel construction for durability and dimensional stability under repeated use
• 0.972-inch nominal measurement diameter covering a common bore size

Compatibility

Designed as a working-class plug pin gage for inspection of 0.972-inch nominal bores and holes in production machining and quality control applications.

Installation Notes

Plug pin gages are handled by quality control technicians and machinists during part inspection. Clean the gage and the bore being measured before use to avoid false readings caused by chips or coolant residue. Store the gage in a protective case away from other metal tooling to prevent nicks or wear to the gage surface. Periodic recalibration against a certified master gage is recommended to confirm the gage remains within its stated tolerance class.