Spi 29-813-3 Class Zz Plus Plug Gage 0.813 Inch

Product Description

The SPI 29-813-3 is a Class ZZ Plus plug gage designed to verify bore and hole dimensions to a nominal diameter of 0.813 inches with a tolerance of 0.0002 inches. Built from steel for durability and dimensional stability, this go/no-go style gage is a standard tool in precision measurement workflows. It is used to confirm that machined holes fall within specified limits, providing fast and reliable pass/fail results without the need for additional measuring instruments. Machinists, quality control technicians, and tool room professionals rely on this type of gage for in-process and final inspection tasks.

This plug gage is suited for shop floor and inspection room environments where bore tolerances must be verified quickly and accurately. It is appropriate for use on drilled, reamed, or bored holes in metal components across general machining, aerospace, automotive, and manufacturing applications. The Class ZZ Plus designation indicates a tighter manufacturing tolerance on the gage itself, making it suitable for applications that demand greater measurement confidence than standard Class ZZ gages provide.

Key Features

• Nominal measurement diameter of 0.813 inches for consistent bore verification
• Tolerance of 0.0002 inches meets Class ZZ Plus precision requirements
• Steel construction provides wear resistance and long service life
• Compact and lightweight at 0.2 pounds for easy one-handed use
• Delivers fast pass/fail results without calculation or readout devices

Compatibility

Designed as a standard Class ZZ Plus plug gage for use in any inspection or machining application requiring bore verification at a nominal diameter of 0.813 inches.

Installation Notes

Plug gages are handled and used by machinists and quality control technicians and do not require installation in the traditional sense. Clean the gage and the bore being checked before use to avoid false readings caused by debris or coolant residue. Store the gage in its case or protected holder when not in use to prevent wear to the gaging surfaces. Never force the gage into a bore, as this can damage both the gage and the workpiece.