Detailed Product Description pressure gauges decription:Case sizes: 1.5", 2", 2.5", 3" and 4" Case metarial: black ABS case Tube and socket: brass, stainless steel, steel with nickel plated, 316 stainless steel, phosphor bronze and more Oil: glycerol /Movement: brass, stainless steel Pointer: black aluminum and adjustable micrometerConnection: 1/8", 1/4", 3/8",1/2", BSP, NPT or BSPT M14X1.5 M10 ...