Brass movement with C shaped Bourdon tube. 1/8 NPT male connection. For use with air, gas, oil or water. Black enameled aluminum pointer, white aluminum dial and temperature compensating polycarbonate window. Glycerin filled to dampen pulse and vibration. Accuracy ASME/ANSI B40.1 Grade A 2-1-2. Bourdon Tube C-shaped, Recommended Use Air, gas, oil, water, Window Material Temperature compensating polycarbonate, Accuracy ASME/ANSI B40.1 Grade A 2-1-2, Movement Brass, Pointer Black enameled aluminum, Gauge Diameter in. 1 1/2, Mount Type Back, Range PSI 0-200, Fill Material Glycerin, Connection Size in. 1/8 Male NPT, Dial White Aluminum.