The AC4000 from Acuity Inc., Fremont, CA, is a very stable low-pressure MEMS sensor module with pressure ratings down to 2.5 mbar F.S. Targeted at low-pressure industrial measurement, medical, and HVAC instrumentation applications, the sensor module is fully calibrated and amplified and is a high zero-stability replacement for many existing sensors. Sensors are available with both analog and digital outputs and have high performance and reliability.