These differential pressure gauges can be used for the measurement of inviscid and non-crystallising liquids and gases.
The steel case contains two independently indicating Bourdon tube measuring systems. Both pointers turn around the same axle and give + and - pressure separately.
The low-pressure is displayed by the pointer, that forms the dial. The pressure difference between the low and high pressure side is given on this dial which may not exceed 50% of the full measuring range. Furthermore, the two individual pressure values can also be directly read.