Spi 29-488-4 Class Zz Plus Plug Gage 0.488 in Steel

Product Description

The SPI 29-488-4 is a Class ZZ Plus plug gage machined to a nominal diameter of 0.488 inches with a tolerance of 0.0002 inches. Plug gages of this class are used to verify whether a hole or bore meets a specified diameter tolerance by checking go/no-go acceptance criteria. The 29-488-4 is constructed from steel, providing the wear resistance and dimensional stability required for repeated use in production or inspection environments. Machinists, quality control technicians, and tool-and-die professionals use Class ZZ plug gages for general-purpose inspection tasks where close but not ultra-precision tolerances apply.

This gage is suited for use in machine shops, fabrication facilities, and manufacturing lines where hole diameter verification is part of standard quality inspection. The 0.488-inch nominal size covers a range of common bore and hole applications in both light and heavy manufacturing. It is appropriate for use with steel, aluminum, and other standard workpiece materials where dimensional conformance must be confirmed before assembly or further machining.

Key Features

• Nominal diameter of 0.488 inches for direct go/no-go hole inspection
• Class ZZ Plus tolerance of 0.0002 inches meets general-purpose inspection standards
• Steel construction provides durability and dimensional stability under repeated use
• Compact form factor at 0.2 pounds suits bench and in-line inspection setups
• Single-piece packaging with a minimum order quantity of one unit

Compatibility

Designed as an OEM-style replacement or standard inspection tool for use with any go/no-go gage handle or plug gage set that accepts 0.488-inch diameter members of Class ZZ Plus classification.

Installation Notes

Plug gages require no permanent installation but should be handled and stored with care to avoid contact damage that could alter the precision diameter. Clean both the gage and the bore being inspected before use to prevent false readings caused by debris or burrs. Do not force the gage into an undersized hole, as this can damage the gage face or distort the bore. A licensed metrologist or QC technician should periodically verify gage calibration against a traceable standard in accordance with applicable inspection procedures.