KING INSTRUMENT CO. FLOW METER, P/N 74C-123G081-4-2-3-5-1-4, 3” SCALE TO 12 SCFH, GLASS TUBE, 1/4”’ NPT STAINLESS STEEL FITTINGS AND INLET VALVE, CARBOLOY FLOAT, VITON O-RINGS, CLEANED FOR OXYGEN SERVICE, WITH LATCHING INDUCTIVE RING SENSOR. SENSOR WILL HOLD THE CIRCUIT WHEN THE FLOAT IS ABOVE THE RING SENSOR AND CIRCUIT WILL BREAK WHEN THE FLOAT IS BELOW THE RING SENSOR.