... case center back male connection oil composing:glycerine, silicone oil diameter:1.5",2",2.5",3",4",6". Panel Mount Stainless ... Steel Liquid Filled Glycerine Pressure Gauge 1. Diameter: 1 ½", 2", 2 ½ ",3",4 ... ",1/2",NPT,BSPT,BSP;6.Connection: bottom connection, center back male connection;7.Range:0~10,000psi;8.Scale:psi ...