Spi 19-507-3 Class Zz Minus Plug Pin Gage 0.507 in

Product Description

The SPI 19-507-3 is a Class ZZ minus plug pin gage with a 0.507-inch nominal diameter, manufactured from steel for durability in shop and inspection environments. It is used to verify hole sizes by checking that a bore does not exceed its minimum acceptable limit. The minus designation means the gage is ground to the lower boundary of the tolerance band, making it suitable for go/no-go inspection workflows where tight dimensional control is required. With a tolerance of 0.0002 inches, this gage delivers reliable measurement accuracy for precision quality control applications. It is handled by machinists, quality technicians, and tool room personnel.

This plug pin gage is appropriate for use in precision manufacturing, machine shops, tool rooms, and quality inspection stations. It is used to check drilled, reamed, or bored holes during in-process and final inspection. The 0.507-inch diameter makes it suitable for applications requiring verification of holes in that size range across a variety of materials and component types. Individual unit packaging makes it easy to add to an existing gage set or to replace a worn or damaged single gage in a collection.

Key Features

• Class ZZ tolerance class — the most common standard for general-purpose plug gages in production inspection
• Minus designation — ground to the lower tolerance boundary for no-go or minimum-limit checking
• 0.0002-inch tolerance for consistent, repeatable dimensional verification
• Steel construction for wear resistance in regular shop use
• 0.507-inch nominal diameter for precise hole size verification

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use in general-purpose hole inspection applications requiring a 0.507-inch diameter gage member.

Installation Notes

Plug pin gages are handled by quality control technicians and machinists during inspection procedures — they are not installed in a system but are used as a handheld measurement tool. Keep the gage clean and lightly oiled when not in use to prevent corrosion and wear. Do not force the gage into an undersized hole, as this can damage the gage surface and compromise measurement accuracy. Store separately from other metal tooling to avoid nicks or surface damage that would affect calibration.