Spi 19-778-0 Class Zz Minus Plug Pin Gage 0.778 in

Product Description

The SPI 19-778-0 is a Class ZZ minus plug pin gage machined to a 0.778-inch nominal diameter with a tolerance of 0.0002 inches. Plug pin gages are GO/NO-GO inspection tools used to verify that a drilled, reamed, or bored hole falls within a specified diameter tolerance. The Class ZZ designation indicates a working-grade gage suitable for production floor inspection rather than master or reference-grade measurement. The minus configuration means the gage is ground below nominal, following standard minus-tolerance practice for GO-type members. This tool is used by machinists, quality control technicians, and tool-and-die professionals.

This gage is suited for dimensional inspection of machined holes in manufacturing and fabrication environments. It is commonly used on the production floor to verify hole size conformance before assembly. The 0.778-inch diameter targets bored or reamed holes in that nominal range. Steel construction provides the hardness and wear resistance required for repetitive gage use in machine shop and quality assurance applications.

Key Features

• Class ZZ working-grade tolerance for production inspection use
• Minus plug configuration ground below nominal diameter
• 0.778-inch nominal diameter with 0.0002-inch tolerance
• Steel construction for durability and wear resistance
• Single-piece pin gage format for straightforward GO-type hole checking

Compatibility

Designed as a working-grade plug pin gage for dimensional inspection of machined holes at or near 0.778-inch nominal diameter in production and quality control settings.

Installation Notes

Plug pin gages are handled and used by machinists and quality control inspectors — no power tools or utility shutoffs are required. Keep the gage clean and lightly oiled when not in use to prevent corrosion and maintain dimensional accuracy. Do not force the gage into an undersized hole, as this can damage the gage surface and compromise measurement integrity. Store separately from other tooling to avoid contact damage to the ground surface.