Spi 29-374-6 Class Zz Plus Plug Gage 0.374 Inch

Product Description

The SPI 29-374-6 is a Class ZZ Plus plug gage designed for go/no-go inspection of holes and bores with a nominal diameter of 0.374 inches. Built from steel and held to a tolerance of 0.0002 inches, this gage provides reliable pass/fail verification during in-process and final inspection. Class ZZ designates a standard commercial tolerance grade, making this gage appropriate for general-purpose production inspection where tight calibration traceability is required. Machinists, quality technicians, and toolroom personnel use plug gages like this one to confirm that drilled, reamed, or bored holes conform to engineering specifications without relying on variable measurement instruments.

This plug gage is suited for use in machine shops, manufacturing cells, and quality control environments handling precision metalwork, fabrication, or assembly operations. It is particularly useful when inspecting holes destined for press-fit pins, dowels, fasteners, or other close-tolerance components. The 0.374-inch diameter targets a specific bore size common in production environments requiring consistent, repeatable attribute gauging.

Key Features

• Class ZZ Plus tolerance grade for general commercial inspection applications
• 0.374-inch nominal measurement diameter for consistent bore verification
• 0.0002-inch tolerance provides precise pass/fail gauging
• Steel construction for durability and wear resistance in production use
• Compact and lightweight at 0.2 pounds for easy bench or floor use

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for any go/no-go inspection application requiring a 0.374-inch diameter Class ZZ Plus gage in steel.

Installation Notes

Plug gages are handled and applied by quality technicians or machinists and require no permanent installation. Clean the gage and bore surfaces before use to prevent measurement error or gage wear. Store the gage in a protective case away from other tooling to avoid damage to the precision-ground surface. Periodic calibration against a traceable standard is recommended to maintain measurement integrity over time.