Spi 29-646-7 Class Zz Plus Plug Gage 0.646 in Dia

Product Description

The SPI 29-646-7 is a Class ZZ Plus plug gage designed to verify bore and hole diameters to a nominal measurement of 0.646 inches. Built from steel, this go/no-go style gage delivers a tolerance of 0.0002 inches, making it suitable for dimensional inspection work where close tolerances are required. Machinists, quality control technicians, and toolroom professionals use plug gages like this one to confirm that drilled, reamed, or bored holes fall within specified limits before parts advance to the next stage of production or assembly.

Class ZZ Plus plug gages are commonly used in production and inspection environments where standard workshop accuracy is required. This gage is appropriate for checking hole diameters in metal, plastic, and composite workpieces across light manufacturing, machining, and fabrication settings. Its compact size and steel construction make it durable for repeated use on the shop floor or in a dedicated inspection area.

Key Features

• Nominal measurement diameter of 0.646 inches for precise bore verification
• Class ZZ Plus tolerance rating of 0.0002 inches for consistent dimensional inspection
• Steel construction for durability and resistance to wear in production environments
• Single-piece design suited for go/no-go inspection workflows
• Lightweight at 0.2 pounds for easy handling during repetitive inspection tasks

Compatibility

Designed as a standard Class ZZ Plus plug gage for use with any inspection or quality control application requiring a 0.646-inch nominal bore diameter check.

Installation Notes

Plug gages are handled and used by quality control technicians and machinists — no power tools or electrical shutoff is required. Keep the gage clean and lightly oiled when not in use to prevent corrosion and maintain accuracy. Do not force the gage into a bore; if resistance is felt, the hole is likely undersize. Store the gage in a protective case away from temperature extremes to preserve calibration integrity.