For whatever you face in a day, the HeartStart MRx is built to be tough and ready for action. The HeartStart MRx is designed to meet stringent test requirements including spraying water, military helicopter vibration, mechanical shock, one-meter drop, electro-magnetic compatibility, and extreme environmental conditions (temperature, humidity and altitude). In addition, the same MRx model that we ship to all EMS customers has passed an extensive battery of tests, performed by the US military, to achieve aeromedical air-worthiness certification. These military-level tests include:  baseline performance and durability, electrical safety, vibration, electro-magnetic compatibility, climate, altitude, rapid decompression, explosive atmosphere, acceleration, and in-flight performance evaluations.