Spi 19-858-0 Class Zz Minus Plug Pin Gage 0.858 in

Product Description

The SPI 19-858-0 is a Class ZZ minus plug pin gage machined from steel, used to verify the dimensional accuracy of drilled, reamed, or bored holes in manufactured parts. The gage measures 0.858 inches in diameter and carries a minus tolerance of 0.0002 inches, placing it within Class ZZ specification for go/no-go inspection work. It is a standard tool in quality control environments, machine shops, and manufacturing facilities where hole diameter verification is part of the production inspection process. Machinists, quality technicians, and tooling specialists use plug gages like this one to confirm that holes fall within print tolerances before parts proceed to assembly.

This gage is suited for use in production inspection, incoming material inspection, and toolroom applications where a 0.858-inch nominal hole diameter must be verified. Class ZZ gages are designed for use with less precise work tolerances and are the most common class for general inspection of commercial-grade parts. The minus designation means the gage is ground to the low side of the nominal diameter, making it appropriate as a go gage in a standard go/no-go inspection setup.

Key Features

• 0.858-inch nominal diameter for direct hole size verification
• Class ZZ specification for general commercial inspection applications
• Minus tolerance ground to 0.0002 inches below nominal diameter
• Steel construction for durability and dimensional stability
• Single-piece pin gage format for straightforward go/no-go use

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use in any inspection application requiring verification of a 0.858-inch nominal hole diameter.

Installation Notes

Plug pin gages are handled and used by machinists and quality control technicians and require no permanent installation. Clean the gage and the hole to be measured before use to prevent contamination from affecting the reading. Do not force the gage into an undersized hole, as this can damage both the gage and the workpiece. Store the gage in a protective case when not in use to preserve its ground surfaces and dimensional integrity.