Spi 19-812-7 Class Zz Minus Plug Pin Gage 0.812 in

Product Description

The SPI 19-812-7 is a Class ZZ minus plug pin gage with a nominal diameter of 0.812 inches, manufactured from steel. It is used to verify bore and hole dimensions by checking whether a machined feature falls within the required tolerance band. Class ZZ is the standard commercial-grade classification for go/no-go inspection work in general manufacturing and quality control environments. The minus designation indicates the gage is ground to the lower boundary of the tolerance zone. With a tolerance of 0.0002 inches, this gage delivers reliable dimensional verification for production inspection tasks. Machinists, quality technicians, and tool-and-die professionals are the primary users.

This pin gage is suited for inspection of drilled, reamed, or bored holes in ferrous and non-ferrous workpieces across light manufacturing, job shop, and production floor environments. It is used as a standalone go or no-go member or as part of a pin gage set program. Typical applications include incoming inspection, in-process quality checks, and final part verification where a 0.812-inch nominal bore diameter is specified on the print.

Key Features

• Class ZZ tolerance grade for general commercial inspection use
• Minus designation ground to the lower boundary of the tolerance zone
• 0.0002-inch tolerance for consistent dimensional verification
• 0.812-inch nominal diameter for direct bore and hole inspection
• Steel construction for durability and wear resistance in production environments

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use in go/no-go inspection fixtures and pin gage sets requiring a 0.812-inch nominal diameter member.

Installation Notes

Pin gages should be handled with clean, dry hands or lint-free gloves to prevent corrosion from skin oils. Before use, verify the gage and workpiece are at the same ambient temperature to avoid thermal expansion errors. Store in a protective case away from abrasive materials to preserve the ground surface finish. Inspection personnel should follow applicable dimensional metrology procedures per shop quality standards.