Spi 19-939-8 Class Zz Minus Plug Pin Gage 0.939 in

Product Description

The SPI 19-939-8 is a Class ZZ minus plug pin gage with a nominal diameter of 0.939 inches, manufactured from steel for durability in shop-floor measurement environments. This gage is used to verify that a hole or bore meets minimum acceptable size requirements. The minus tolerance design means the gage is manufactured to the lower tolerance boundary, making it appropriate for go/no-go inspection workflows where confirming minimum hole size is the priority. With a tolerance of 0.000200 inches, it meets the dimensional accuracy standards expected for Class ZZ tooling used in general-purpose inspection applications.

This plug pin gage is suited for quality control technicians, machinists, and tool-room inspectors working in manufacturing, fabrication, or precision machining environments. It is used to check hole diameter conformance on machined parts, castings, and fabricated components. The 0.939-inch diameter makes it appropriate for medium-bore inspection tasks in both production and incoming-inspection settings.

Key Features

• Class ZZ minus tolerance designation for go/no-go minimum hole size verification
• Nominal diameter of 0.939 inches for medium-bore inspection
• Tolerance of 0.000200 inches for precise dimensional conformance checking
• Steel construction for wear resistance and dimensional stability
• Single-piece packaging suitable for individual replacement or tooling additions

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use in general-purpose hole inspection applications where a nominal bore diameter of 0.939 inches is being verified.

Installation Notes

Plug pin gages are handled and used by quality control technicians and machinists following standard metrology practices. Keep the gage clean and lightly oiled when not in use to prevent corrosion and wear. Do not force the gage into a hole; apply only light hand pressure during inspection to avoid damaging the gage or the workpiece. Store in a protective case away from temperature extremes to maintain dimensional stability.