Sensor module for recording the heart rate.Sensor/finger clip not included.1.InstructionThis module is mainly to measure heart rate. In order to complete this function, just connect easily to a microcontroller and compile corresponding program. 2.ParametersWorking voltage: 3.3---5VWorking current: 800uARange of working temperature: 0--60 3. FeaturesWith DC-DC isolated power, safe low voltagePrecise testing data"