Spi 29-768-9 Class Zz Plus Plug Gage 0.768 in

Product Description

The SPI 29-768-9 is a Class ZZ Plus plug gage designed for precision hole measurement in machining, inspection, and quality-control applications. Built to a nominal diameter of 0.768 inches with a tolerance of 0.0002 inches, this gage provides reliable go/no-go verification for drilled, reamed, or bored features. The steel construction delivers the hardness and dimensional stability required for repeated use in shop-floor and inspection-room environments. Machinists, toolmakers, and quality technicians use plug gages like this one to confirm that a hole falls within the specified size range before a part moves to the next stage of production.

This gage is suited for use in manufacturing facilities, machine shops, and inspection departments where tight-tolerance hole verification is required. It is appropriate for both production-line spot checks and incoming or final inspection workflows. The 0.768-inch nominal size makes it a practical choice for applications involving close-tolerance bores in ferrous and non-ferrous components. A single gage is supplied per package, making it easy to stock as a replacement or supplement to an existing gage set.

Key Features

• Nominal measurement diameter of 0.768 inches for direct hole-size verification
• Class ZZ Plus tolerance rating of 0.0002 inches for precision go/no-go inspection
• Steel construction for hardness, wear resistance, and dimensional stability
• Single-piece package suitable for individual replacement or set expansion
• Compact and lightweight at 0.2 pounds for easy handling during inspection

Compatibility

Designed as a standard Class ZZ Plus plug gage for use in general precision inspection applications requiring 0.768-inch nominal bore verification.

Installation Notes

Plug gages are handled and used by machinists, toolmakers, and quality-control inspectors — no power tools or energy isolation is required. Keep gage surfaces clean and lightly oiled when not in use to prevent corrosion. Do not force the gage into a bore; if resistance is felt, the hole is undersized and should be re-inspected before proceeding. Store in a protective case away from temperature extremes to maintain calibration integrity.