The MPB Series 650 range of Variable Area Flowmeters are suitable for measuring the instantaneous flow rate of virtually any process liquid or gas. The principle of operation of the variable area flowmeter is quite simple:- The height attained by the float in its tapered flow tube is directly related to a calibrated scale. The MPB Series 650 flowmeter has rear facing connections. The flowmeter can be supplied for insert mounting into a panel cutout or surface mounting.