Spi 19-724-4 Class Zz Minus Plug Pin Gage 0.724 in

Product Description

The SPI 19-724-4 is a Class ZZ minus plug pin gage designed to verify that a hole or bore meets minimum size requirements within tight dimensional tolerances. Machined from steel, this go/no-go style gage checks a nominal diameter of 0.724 inches with a tolerance of 0.0002 inches, making it appropriate for quality control and inspection work where precise bore verification is required. It is used by machinists, tool and die makers, and QC inspectors working in machine shops, manufacturing facilities, and production environments where hole sizing must be confirmed before assembly.

Class ZZ plug gages are the most common grade for general shop-floor inspection. This minus-type gage is used as a go gage, entering a hole that meets minimum acceptable diameter. At 0.724 inches nominal diameter, it fits inspection applications for medium-bore components in metal fabrication, machined part verification, and production quality assurance workflows. The compact form factor and steel construction make it durable for repeated use in industrial environments.

Key Features

• Class ZZ tolerance class — standard grade for general shop inspection and go/no-go bore checking
• Minus designation — functions as a go gage to confirm minimum acceptable hole diameter
• 0.724 inches nominal diameter with 0.0002 inches tolerance for reliable dimensional verification
• Steel construction for durability and dimensional stability under repeated use
• Single-piece pin design for straightforward handling and fast inspection cycles

Compatibility

Designed as an OEM-style Class ZZ plug pin gage for use in standard bore inspection applications requiring a 0.724 inch nominal diameter check.

Installation Notes

Plug pin gages are handled and stored by metrology technicians, QC inspectors, and skilled machinists — not installed in mechanical systems. Store the gage in a protective case away from moisture and temperature extremes to preserve dimensional accuracy. Clean the gage pin and the bore being checked before use to prevent wear and false readings. Do not force the gage into an undersized hole, as this will damage the gage surface and compromise calibration.