Spi 29-789-5 Class Zz Plus Plug Gage 0.789 in Dia

Product Description

The SPI 29-789-5 is a Class ZZ Plus plug gage designed to verify bore and hole diameters to a nominal size of 0.789 inches with a tolerance of 0.0002 inches. Plug gages of this class are used in go/no-go inspection routines to confirm that machined features fall within specified dimensional limits. The steel construction provides durability in shop-floor environments. Machinists, quality control technicians, and tool room professionals use this type of gage during in-process and final inspection of drilled, reamed, or bored features.

This plug gage is suited for precision dimensional inspection in manufacturing, fabrication, and machining operations. Class ZZ Plus gages occupy a tighter tolerance class than standard Class ZZ, making this gage appropriate for applications where close process control is required. It is used in both job-shop and production environments where consistent bore verification is part of a documented quality process.

Key Features

• Nominal measurement diameter of 0.789 inches for direct bore verification
• Class ZZ Plus tolerance rating of 0.0002 inches for close-tolerance inspection work
• Steel construction for wear resistance and dimensional stability under shop conditions
• Compact, single-unit form factor suitable for bench or in-line inspection stations

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for any go/no-go inspection setup requiring a 0.789-inch nominal bore diameter check at Class ZZ Plus tolerance.

Installation Notes

Plug gages should be handled with clean, dry hands or lint-free gloves to prevent corrosion from skin oils. Store the gage in its case or on a clean surface away from abrasive materials when not in use. Calibration and use should follow ASME B89.1.5 or the applicable shop quality plan. Do not force the gage into a feature; apply only light, consistent hand pressure to avoid damage to the gage or the workpiece.