The pulse sensor is a sensor used to test the heart rate. Students, artists, athletes, creators, games or mobile terminal developers can develop interactive works related to heart rate. The sensor can be worn on a finger or earlobe and connected to the Ard via a wire. It also has an open source app that displays your heart rate in real time. The essence is an optical heart rate sensor that integrates an amplifying circuit and a noise canceling circuit. Supply voltage: 3V or 5V.