... Glass window 3. Brass internal, black steel pressure gauge 4. OEM General Pressure Gauge: (1)Diameter: 1-1/2 ... steel, plastic (3)Accuracy: 3-2-3%General Pressure Gauge:(1)Diameter: 1-1/2", 2", 2 ... 8)Accuracy: 3-2-3%(9)Use: Measuring pressure on copper and copper alloy non-corrosive, non-explosive, ... non-crystalline, not precipitate the gas or liquid pressure. Such as water, such as air. Customers brands ...