Spi 29-030-4 Class Zz Plus Plug Gage 0.03 in Steel

Product Description

The SPI 29-030-4 is a Class ZZ Plus plug gage designed for precision bore and hole measurement in machining and quality-control applications. Measuring a nominal diameter of 0.03 inches with a tolerance of 0.0002 inches, this gage delivers the accuracy required for tight-tolerance inspection work. Constructed from steel for durability and dimensional stability, the 29-030-4 is a go/no-go style reference tool used to verify that machined holes meet specified diameter requirements. Machinists, toolmakers, and quality-control technicians rely on Class ZZ plug gages as a standard part of in-process and final inspection workflows.

This gage is suited for inspection of small-diameter bores in precision machined components across aerospace, automotive, medical device, and general manufacturing environments. The 0.03-inch diameter makes it appropriate for very fine bore verification where standard pin gages or calipers lack the resolution needed to confirm conformance. It is commonly used at inspection stations, on the shop floor, or at receiving inspection to validate vendor-supplied parts.

Key Features

• 0.03-inch nominal measurement diameter for small-bore inspection
• Class ZZ Plus tolerance of 0.0002 inches for precision go/no-go verification
• Steel construction for dimensional stability and wear resistance
• Compact, single-piece design suited for bench or floor inspection use
• Packaged individually — quantity of one per unit

Compatibility

Designed as a standard Class ZZ Plus plug gage for use in any inspection application requiring precision verification of a 0.03-inch nominal bore diameter.

Installation Notes

Plug gages are inspection tools and do not require installation. Handle with clean, dry hands or lint-free gloves to prevent corrosion and dimensional contamination. Store in a protective case away from temperature extremes to maintain calibration integrity. Periodic recertification against NIST-traceable standards is recommended per applicable quality system requirements.