When working with high-pressure gas or liquid, you'll want to know that your system is leak-free and secure. This 42004 pressure gauge comes with a 3 1/8-inch steel casing so you can easily read the pressure levels. The gauge casings are built for rugged use. This gauge reads within a 1% accuracy for critically charged systems like industrial refrigerants and air-conditioning units. The brass ports attach to color-coded 60-inch hoses for firm and reliable connections.