Spi 29-376-1 Class Zz Plus Plug Gage 0.376 in

Product Description

The SPI 29-376-1 is a Class ZZ Plus plug gage designed for precision bore and hole measurement in machine shops, toolrooms, and manufacturing environments. Built from steel, this gage checks whether a 0.376-inch diameter hole or bore falls within acceptable tolerance limits. The Class ZZ designation indicates a working-grade tolerance of 0.0002 inches, making it appropriate for inspection and quality control tasks where moderate precision is required. Machinists, tool and die makers, and quality technicians use plug gages like this one to verify that drilled, reamed, or bored features conform to print dimensions before assembly.

This plug gage is suited for use in production inspection, incoming material checks, and toolroom verification. It is commonly used on steel, aluminum, and cast components where hole diameter acceptance criteria must be confirmed quickly and reliably. The go/no-go style of inspection it supports is standard practice in manufacturing facilities, job shops, and quality labs handling tight-tolerance mechanical parts.

Key Features

• Class ZZ Plus tolerance grade at 0.0002 inches for reliable working-grade inspection
• Nominal measurement diameter of 0.376 inches for precise hole acceptance checks
• Steel construction for durability in shop environments
• Compact and lightweight at 0.2 pounds for easy hand use
• Single-piece package quantity suitable for individual toolroom or bench use

Compatibility

Designed as a working-grade plug gage for standard hole and bore inspection applications requiring a 0.376-inch nominal diameter check per Class ZZ Plus tolerance specifications.

Installation Notes

Plug gages are installed and used by machinists, quality technicians, and toolroom personnel — no power tools or energy isolation is required. Handle the gage with clean, dry hands or cotton gloves to prevent corrosion from skin oils, and store it in a protective case when not in use. Do not force the gage into an undersized hole, as this can damage both the gage and the workpiece. Calibrate and verify gage condition periodically per your facility quality plan.