The differential pressure gauges series MNS-DDP are pressure gauges that has double Bourdon system for measure the difference between two pressures. Two models are available : MNSTSS-DDP for general uses ; MNSS-DDP corrosion-proof. The MNSTSS-DP type is suitable to measuring the uncorrode medium and the MNSS-DDP type could be used in corrode environments. The instruments has two independent measuring systems. The measured pressure deflects the elastic elements, displacements then take place to actuate gear mechanisms throught linkages to carry two pointers traveling over instrument dial, and an auxiliary dial shows the pressure difference (ΔP).