Brass movement with C shaped Bourdon tube. 1/4in. 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. Connection Size in. 1/4 Male NPT, Gauge Diameter in. 4, Bourdon Tube C-shaped, Fill Material Glycerin, Accuracy ASME/ANSI B40.1 Grade A 2-1-2, Pointer Black enameled aluminum, Range PSI 0-3,000, Recommended Use Air, gas, oil, water, Max. PSI 3,000, Mount Type Stem, Movement Brass, Window Material Temperature compensating polycarbonate, Dial White aluminum.