... scale dry pressure gauge bottom brass connection diameter:1.5",2",2.5",3",4",6". Black Steel Case Dual Scale Dry ... Pressure Gauge 1. Diameter: 1 ½", 2", 2 ½ ",3",4",6";2.Case: black steel case;3.Window:glass ... , acrylic, polycarbonate;4.Internal: brass, stainless steel ...