Spi 29-512-1 Class Zz Plus Plug Gage 0.512 in

Product Description

The SPI 29-512-1 is a Class ZZ Plus plug gage designed to verify bore and hole diameters with consistent, repeatable accuracy. Built from steel, this go/no-go style gage checks a nominal diameter of 0.512 inches to a tolerance of 0.0002 inches. Class ZZ is the standard tolerance grade for general-purpose inspection of production parts. Machinists, quality technicians, and tool-room professionals use plug gages like this one to confirm that drilled, reamed, or bored holes meet print specifications before parts advance through the production process.

This gage is suited for dimensional inspection on the shop floor or in a quality lab. It is appropriate for use in manufacturing environments where hole-size verification is required on ferrous and non-ferrous workpieces. The 0.512-inch diameter range targets applications where close-tolerance bore inspection is part of a standard quality-control workflow. At 0.2 pounds, it is lightweight and easy to handle during repetitive inspection tasks.

Key Features

• Nominal measurement diameter of 0.512 inches for precise bore verification
• Class ZZ Plus tolerance grade at 0.0002 inches for general production inspection
• Steel construction for durability and dimensional stability during repeated use
• Lightweight at 0.2 pounds for comfortable single-handed operation
• Single-piece package quantity — ready to use out of the box

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for general-purpose bore inspection applications requiring a 0.512-inch nominal diameter at Class ZZ Plus tolerance.

Installation Notes

Plug gages are handled and used by machinists and quality-control technicians — no power tools or electrical shutoff procedures apply. Clean the gage and the bore being checked before use to prevent debris from affecting the reading. Do not force the gage into an undersized hole, as this can damage the gage or the workpiece. Store in a protective case away from temperature extremes to maintain dimensional accuracy.