The testo 512 0 200hpa for simultaneous pressure and flow measurement the device has two switch able units for current flow m s and fpm for pressure eight units are adjustable kpa hpa pa mm h2o mmhg psi inhg and inh2o the damping is adjustable for sliding purposes the density compensation is integrated the displayed actual value with the hold button can be held in the display the min max value can be displayed and stored in the device