Spi 29-446-2 Class Zz Plus Plug Gage 0.446 in

Product Description

The SPI 29-446-2 is a Class ZZ Plus plug gage designed to verify hole diameters to a nominal size of 0.446 inches with a tolerance of 0.0002 inches. Built from steel, this go/no-go style gage gives machinists, quality technicians, and precision tradespeople a fast, reliable method for confirming bore dimensions during inspection or in-process checks. Class ZZ is the standard tolerance grade for general-purpose plug gages used in production and shop-floor measurement where repeatable, accurate diameter verification is required.

This plug gage is suited for use in machine shops, manufacturing facilities, and toolrooms where hole diameter conformance must be confirmed against a defined tolerance. It is appropriate for inspecting drilled, reamed, or bored holes in metal, plastic, or composite workpieces. At 0.446 inches nominal diameter, the 29-446-2 falls within the common range used for precision fastener clearance holes, dowel pin fits, and similar close-tolerance applications. Quality control inspectors and CNC machinists routinely use this type of gage as part of a standard inspection process.

Key Features

• Nominal measurement diameter of 0.446 inches for precise bore verification
• Class ZZ Plus tolerance of 0.0002 inches for reliable general-purpose inspection
• Steel construction for durability and dimensional stability in shop environments
• Compact and lightweight at 0.2 pounds for easy single-hand use
• Individual unit packaging suitable for bench, floor, or toolroom use

Compatibility

Designed as an OEM-style replacement or direct-use Class ZZ plug gage for standard shop inspection of 0.446-inch nominal diameter bores in production and quality control environments.

Installation Notes

Plug gages should be handled by metrology or quality control personnel following standard gage-handling procedures. Clean and lightly oil the gage before and after each use to prevent corrosion and maintain accuracy. Do not force the gage through a hole; excessive insertion force can damage both the gage and the workpiece and will produce unreliable results. Store in a protective case away from temperature extremes to preserve dimensional integrity.