4000-50CM is a series 4000 Capsuhelic® differential pressure gauge designed to give fast, accurate indication of differential pressures. The gauge may be used as a readout device when measuring flowing fluids, pressure drop across filters, liquid levels in storage tanks and many other applications involving pressure, vacuum or differential pressure. The pressure being measured is held within a capsule which is an integral part of the gauge. Typical applications include fluid flow, liquid storage tanks, filter pressure drops, vacuum or differential pressure.