Spi 29-406-6 Class Zz Plus Plug Gage 0.406 in

Product Description

The SPI 29-406-6 is a Class ZZ Plus plug gage used to verify the diameter of machined holes to a tight tolerance standard. Designed for go/no-go inspection work, this gage checks whether a hole falls within the specified 0.406-inch diameter range, holding a tolerance of 0.0002 inches. Constructed from steel for durability and dimensional stability, it is a standard hand tool used by machinists, quality control technicians, and tool-and-die professionals in production and inspection environments. Its compact form makes it easy to handle during repetitive part checking on the shop floor or in the inspection room.

This plug gage is suited for dimensional inspection of precision-machined holes in manufacturing, metalworking, and tooling applications. It is commonly used in production shops where hole diameter conformance must be verified against tight tolerances. Class ZZ Plus gages are appropriate for general-purpose inspection of commercial-grade workpieces. Technicians use this gage as part of standard incoming, in-process, or final inspection workflows.

Key Features

• Class ZZ Plus tolerance class for general-purpose hole inspection
• 0.406-inch nominal diameter for consistent, repeatable measurement
• Tolerance of 0.0002 inches for precise go/no-go verification
• Steel construction for long service life and dimensional stability
• Lightweight at 0.2 pounds, easy to handle during repetitive inspection

Compatibility

Designed as an OEM-style precision inspection tool for use with 0.406-inch nominal diameter holes in standard machined components and fixtures.

Installation Notes

Plug gages are used by machinists and quality control inspectors and require no special installation. Ensure the workpiece is free of chips, burrs, and coolant before gaging to avoid false readings or gage damage. Store the gage in its case or a protected location when not in use to preserve its calibrated surfaces. Periodic recalibration against certified masters is recommended to maintain measurement accuracy.