74055660
May 4, 1990
Jul 16, 1991
liquid and gas meters, venturi tubes, pitot tubes, indicating rate gauges, recording rate gauges, combination recording and indicating rate gauges, gauges for indicating and recording the loss of head through a filter and rate of flow or both, gauges indicating or recording rate of flow and totalizing the flow, manometers and pitot recorders
Electrical and Scientific Apparatus