Brass movement with C shaped Boudon 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%). NOTE: Image shown is representative of the guage style, not necessarily identical to what will be received.