Spi 29-280-5 Class Zz Plus Plug Gage 0.28 Inch

Product Description

The SPI 29-280-5 is a Class ZZ Plus plug gage designed for precision dimensional inspection of bored holes, drilled passages, and machined apertures. It measures a nominal diameter of 0.28 inches with a tolerance of 0.0002 inches, making it suitable for go/no-go inspection work where tight dimensional control is required. Constructed from steel, this gage provides the wear resistance and dimensional stability expected in production and quality-control environments. Machinists, tool-and-die workers, and quality inspectors use plug gages like this one to verify that a hole has been produced within its specified tolerance range.

The SPI 29-280-5 is used in machine shops, manufacturing facilities, and maintenance environments where hole diameter verification is part of a quality or inspection process. It is appropriate for both incoming inspection of purchased parts and in-process checks during machining operations. The 0.28-inch nominal size positions this gage for use with small-diameter precision holes common in mechanical assemblies, hydraulic components, and similar precision-machined parts.

Key Features

• Class ZZ Plus tolerance rating for reliable go/no-go hole inspection
• 0.28-inch nominal measurement diameter
• 0.0002-inch tolerance for precise dimensional verification
• Steel construction for durability and dimensional stability
• Compact single-piece design suitable for bench or field inspection use

Compatibility

Designed as a standard plug gage for inspecting 0.28-inch nominal diameter holes in machined components across general manufacturing and maintenance applications.

Installation Notes

Plug gages should be handled with clean, dry hands or cotton gloves to prevent corrosion from skin oils. Before use, verify that the gage and workpiece are at the same temperature to avoid measurement error from thermal expansion. Do not force the gage through a hole; excessive insertion force can damage the gage land or the workpiece bore. Store in a protective case away from abrasive materials when not in use.