Spi 19-377-1 Class Zz Minus Plug Pin Gage 0.3770 in

Product Description

The SPI 19-377-1 is a Class ZZ minus plug pin gage designed for dimensional inspection of bored holes, machined openings, and precision-fit features. It measures a nominal diameter of 0.3770 inches with a minus tolerance of 0.000200 inches, meaning the gage is manufactured to the low side of the nominal dimension. Made from steel, this gage is used by machinists, quality control technicians, and tool-and-die professionals who need a reliable go or no-go reference for hole verification on production floors, inspection benches, and job shops.

Class ZZ minus plug gages are the standard choice for general-purpose inspection work where tight tolerance verification is required. This gage suits applications in metalworking, fabrication, and precision machining environments. It is typically used as a go gage to verify that a drilled or reamed hole meets minimum acceptable size before a part advances to the next production stage. The 0.3770-inch nominal size places it in a common range for threaded insert bores, locating pin holes, and dowel pin fits in both ferrous and non-ferrous workpieces.

Key Features

• Nominal measurement diameter of 0.3770 inches for precise hole inspection
• Minus tolerance of 0.000200 inches, manufactured to the low side of nominal
• Class ZZ designation for general-purpose inspection and production use
• Steel construction for durability in workshop and inspection environments
• Single-piece unit with no assembly required straight out of packaging

Compatibility

Designed as a general-purpose Class ZZ minus plug pin gage for use with standard gage handle sets and pin gage holders that accept 0.3770-inch diameter pins in typical inspection and quality control applications.

Installation Notes

Plug pin gages are handled and used by machinists and QC inspectors and do not require permanent installation. Store the gage in its protective sleeve or roll when not in use to prevent surface damage. Clean the gage and the workpiece bore before inspection to remove chips, coolant, and debris that could affect reading accuracy. Do not force the gage into an undersized bore, as this can damage both the gage and the workpiece surface.