Spi 19-221-1 Class Zz Minus Plug Pin Gage 0.221 in

Product Description

The SPI 19-221-1 is a Class ZZ minus plug pin gage machined to a 0.221-inch nominal diameter with a tolerance of 0.0002 inches. Pin gages are single-ended or double-ended cylindrical gauging tools used to verify bore diameter, hole size, and feature location on machined parts. Class ZZ is the standard working-grade tolerance class suited for production floor inspection and general quality control tasks. This gage is manufactured from steel for durability and dimensional stability under repeated use. Machinists, toolmakers, and quality inspection technicians install and maintain these tools as part of a gage pin set or as individual go/no-go references.

This gage is suited for incoming inspection, in-process measurement, and final inspection applications across general manufacturing, tooling shops, and precision machining environments. It is used wherever a 0.221-inch diameter hole or bore must be verified for conformance to print. The minus designation indicates the gage is ground to the lower boundary of the nominal size, making it appropriate for checking minimum material condition on hole features.

Key Features

• Class ZZ working-grade tolerance class for production inspection use
• Nominal diameter of 0.221 inches with a 0.0002-inch tolerance
• Minus designation for lower-boundary dimensional verification
• Steel construction for wear resistance and dimensional stability
• Compact form factor compatible with standard gage pin handles and holders

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use as an individual gauging pin or as a replacement within existing gage pin sets requiring a 0.221-inch diameter member.

Installation Notes

Plug pin gages are handled and stored by metrology or quality inspection personnel following standard gage care procedures. Clean the gage and the workpiece bore before use to prevent false readings from contamination. Store in a protective case away from impact, moisture, and temperature extremes to maintain calibration. Periodic recalibration against a traceable standard is recommended per applicable quality system requirements.