"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. Max. PSI 200, Recommended Use Air, gas, oil, water, Bourdon Tube C-shaped, Accuracy ASME/ANSI B40.1 Grade A 2-1-2, Pointer Black enameled aluminum, Connection Size in. 1/8 Male NPT, Dial White aluminum, Movement Brass, Fill Material Glycerin, Range PSI 0-200, Window Material Temperature compensating polycarbonate, Mount Type Back, Gauge Diameter in. 1 1/2."