Spi 29-385-2 Class Zz Plus Plug Gage 0.385 in

Product Description

The SPI 29-385-2 is a Class ZZ Plus plug gage designed to verify bore and hole dimensions to a nominal diameter of 0.385 inches. Built from steel, this go/no-go style gage delivers a tolerance of 0.0002 inches, making it suitable for inspection work where dimensional accuracy is critical. Machinists, tool-and-die technicians, and quality-control inspectors use plug gages like this to confirm that drilled, reamed, or bored holes fall within specified limits. The Class ZZ designation indicates a working-grade tolerance class appropriate for production-floor inspection of general-tolerance features.

This gage is used in manufacturing, maintenance, and inspection environments wherever a 0.385-inch nominal hole size must be verified. Typical applications include checking drilled or reamed bores in metal components, verifying fixture holes, and performing in-process quality checks on the shop floor. It is suited for both job-shop and production-line settings where consistent, repeatable dimensional verification is required.

Key Features

• 0.385-inch nominal diameter for direct bore verification at that dimension
• 0.0002-inch tolerance consistent with Class ZZ Plus working-gage standards
• Steel construction for durability and wear resistance in shop conditions
• Compact and lightweight at 0.2 pounds for easy handheld use
• Single-piece package quantity for individual replacement or kit supplementation

Compatibility

Designed as a working-grade plug gage for inspection of holes with a 0.385-inch nominal diameter in general manufacturing and maintenance applications.

Installation Notes

Plug gages are handled and used by machinists, inspectors, and metrology technicians — no installation in the mechanical sense is required. Store the gage in a protective case away from moisture and debris to prevent corrosion on the steel surface. Clean the gage and the bore being checked before use to avoid false readings caused by chips or coolant residue. Do not force the gage into an undersized hole, as this can damage the gage surface and compromise calibration.