Measure the air intake filter pressure difference on an industrial air compressor with this -100 to +100 mb range, 0 to 10 volt output differential pressure sensor.
DMD Series
DMD341 Compact Differential Air Pressure Sensor
Small size dp sensor for measuring differential air pressure on HVAC, compress air and pneumatic control systems.
DMD331 Compact Differential Liquid Pressure Sensor
Wet wet differential pressure sensor with a high overpressure rating on both positive and negative pressure side for protection against damage.