The NoShok 200 series 4" (100 mm) pressure gauge has brass wetted parts, a dry circular dial enclosed in a stainless steel 304 case, a lower mount male 1/4" NPT connection, and measures pressure with a single or dual scale with an accuracy of + or - 1%. The brass wetted parts are for measuring non-corrosive liquid and gas pressure. The stainless steel 304 case provides corrosion resistance. The instrument glass lens on the dry 4" dial provides strength and clarity. The dial is white aluminum with black markings, is UV resistant, and has a black finished aluminum pointer. The gauge measures pressure with either a single or a dual scale in inch water column (WC), psi, or oz./square inch. The gauge is accurate to + or - 1% over the entire range of the gauge, American Society of Mechanical Engineers (ASME) B40.100 Grade A accuracy class. The male connection is mounted on the bottom of the gauge and has a 1/4" NPT (National Pipe Thread) rate. The movement is brass and nickel-silver with highly polished bearing surfaces. The gauge has an ultra-sensitive copper alloy diaphragm capsule. The gauge operates in both fluctuating and static pressures up to 90% of the dial range. The ambient temperature for the gauge is 0 to 140 degrees F (-18 to 60 degrees C). The media temperature range is -4 to 140 degrees F (-20 to 60 degrees C). This pressure gauge is suitable for medical, biomedical, HVAC, gas distribution, filtration, burner and gas combustion service, and wastewater treatment applications.Pressure gauges are instruments used to measure the pressure of a gas or liquid inside a vessel and, often, to help ensure the optimal amount of pressure for a given application. Pressure gauges can range from everyday instruments, such as those used to measure the air pressure in a car or bicycle tire, to highly accurate gauges used in mechanical and industrial processing. Most often, pressure gauges measure pressure relative to another reference. For instance, gauge pressure measures pressure relative to ambient air. An example of a pressure gauge measuring relative to ambient air is a tire pressure gauge or a blood pressure gauge. Differential pressure is the difference in pressure between two points, such as when measuring liquid flow along various points in a pipeline. An absolute pressure gauge measures pressure relative to a perfect vacuum, such as an atmospheric or barometric pressure gauge. All types of pressure gauges include either a male or a female mount to connect to the vessel where pressure is being measured, and display results on a dial with varying increments of measure across a given range.NoShok manufactures temperature and pressure measurement instruments, including pressure gauges, transducers and indicators, level transmitters, temperature switches and transmitters, and bimetal thermometers. The company, founded in 1967, is headquartered in Berea, OH.