Datasheet: 
P621 DIFFERENTIAL PRESSURE GAUGE WITH CONTACTService intendedThe
p621 to P625 series are designed to measure differential pressure from 5kPa to 1.5MPa at static pressure up to 5MPa and have electrical contact.
p621 to P625 series are designed to control and alarm for differential pressure, providing right time to replace air and sludge filter during the process.
All features and specifications subject to change without notice, delivery subject to availability, correction of errors and omissions excepted.