Spi 29-273-0 Class Zz Plus Plug Gage 0.273 in

Product Description

The SPI 29-273-0 is a Class ZZ Plus plug gage designed for precision dimensional inspection of cylindrical bores and holes. Manufactured from steel, this go/no-go style gage checks whether a drilled, reamed, or bored hole falls within acceptable tolerance limits. The 29-273-0 measures a nominal diameter of 0.273 inches and holds a tolerance of 0.0002 inches, making it suitable for quality control applications where tight dimensional accuracy is required. Machinists, tool and die makers, and quality control technicians use plug gages like this as a fast, repeatable method for verifying hole size without relying on variable measuring instruments.

This gage is used in machine shops, manufacturing facilities, and precision fabrication environments where hole diameter verification is part of standard inspection workflow. The 0.273-inch diameter suits applications involving small-bore features common in mechanical assemblies, pneumatic components, and precision tooling. Class ZZ Plus designates the tolerance grade, which is appropriate for inspection of commercial-grade workpieces requiring controlled but non-ultra-precision fit verification.

Key Features

• Nominal measurement diameter of 0.273 inches for small-bore inspection
• Class ZZ Plus tolerance grade at 0.0002 inches for reliable go/no-go decision-making
• Steel construction for durability and dimensional stability during repeated use
• Compact and lightweight at 0.2 pounds for easy handling during inspection
• Single-piece package quantity suited for individual workstation or field inspection use

Compatibility

Designed as a Class ZZ Plus plug gage for use in standard bore and hole inspection applications where a 0.273-inch nominal diameter measurement is required.

Installation Notes

Plug gages are installed by hand — no tools are required for use, but proper gage handling practices should be followed to avoid damage to the gage or the workpiece. Clean the bore and gage surfaces before use to prevent debris from affecting readings. Store the gage in its case or protective sleeve when not in use to preserve its tolerance integrity. Periodic recalibration against a certified master is recommended to maintain measurement confidence over time.