Spi 29-728-3 Class Zz Plus Plug Gage 0.728 in

Product Description

The SPI 29-728-3 is a Class ZZ Plus plug gage designed to verify bore and hole diameters with a nominal measurement of 0.728 inches and a tolerance of 0.0002 inches. Machined from steel, this fixed-limit gage provides a reliable go/no-go reference for quality control and inspection tasks on the shop floor or in a metrology environment. Class ZZ is a standard tolerance class for plug gages used in production inspection, making this tool appropriate for checking workpiece holes to drawing specifications. Metrology technicians and quality control inspectors are the primary users of this type of instrument.

This plug gage is suited for production inspection environments where consistent bore verification is required. It is typically used to confirm that drilled, reamed, or bored holes fall within acceptable dimensional limits before parts move to the next stage of manufacturing. The 0.728-inch diameter targets hole sizes common in general machining and fabrication work. The compact form factor makes it easy to handle during high-volume part checks.

Key Features

• Nominal measurement diameter of 0.728 inches for precise bore inspection
• Tolerance of 0.0002 inches meeting Class ZZ Plus gage standards
• Steel construction for durability in production and shop environments
• Fixed-limit design enables fast go/no-go inspection without adjustment
• Single-piece package quantity suitable for individual workstation use

Compatibility

Designed as an OEM-style fixed-limit plug gage for inspecting 0.728-inch nominal diameter bores in general machining and production inspection applications.

Installation Notes

Plug gages are handled by quality control inspectors and metrology personnel, not installed in systems. Before use, clean both the gage and the bore to remove chips, oils, and debris that could affect accuracy. Do not force the gage into a hole; excessive insertion force can damage the gage surface or alter its calibration. Periodic recalibration against certified gage blocks is recommended to confirm dimensional accuracy over time.