Spi 29-276-3 Class Zz Plus Plug Gage 0.276 in

Product Description

The SPI 29-276-3 is a Class ZZ Plus plug gage designed to inspect and verify hole diameters to a nominal size of 0.276 inches with a tolerance of 0.0002 inches. Plug gages are go/no-go inspection tools used in precision machining and manufacturing environments to confirm that bored, drilled, or reamed holes fall within specification. This gage is constructed from steel for dimensional stability and wear resistance. Machinists, quality control technicians, and tool-and-die professionals rely on plug gages like this one as a fast, reliable method for in-process and final inspection without the need for electronic measuring equipment.

This gage is suited for use in machine shops, production floors, and inspection rooms where hole diameter verification is part of standard quality control workflow. It applies to close-tolerance work in industries including aerospace, automotive, and general manufacturing. The 0.276-inch diameter makes it appropriate for inspecting small-bore features where a handheld micrometer or caliper may introduce operator error. It is a single-ended gage intended for manual use in checking one specific nominal diameter.

Key Features

• Nominal measurement diameter of 0.276 inches for precise small-bore inspection
• Class ZZ Plus tolerance rating of 0.0002 inches for reliable go/no-go gauging
• Steel construction for durability and dimensional stability under repeated use
• Compact and lightweight at 0.2 pounds for easy handling during inspection
• Single-piece design suited for integration into standard inspection protocols

Compatibility

Designed as an OEM-style replacement or direct-use inspection gage for applications requiring Class ZZ Plus plug gage verification at a 0.276-inch nominal diameter.

Installation Notes

Plug gages should be handled and stored carefully to avoid nicks, corrosion, or thermal expansion that could affect accuracy. Before use, clean both the gage and the workpiece bore with a lint-free cloth to remove debris and oils. Apply light gage oil when appropriate to extend gage life and protect the steel surface. Calibration and periodic recertification to applicable ASME or ANSI standards should be performed by a qualified metrology technician.