.The 80cm Infrared Proximity Sensor is a General Purpose Type Distance Measuring Sensors, this sensor takes a continuous distance reading and returns a corresponding analog voltage with a range of 10cm (4") to 80cm (30"). Can be used in TVs, personal computers, cars and so on. Features Grove interface compatible Wide supply voltage range: 2.5V7V Interface. This sensor is quite small and use a tiny connector called the Japan Solderless Terminal (JST) connector. These connectors have three wires: ground, vcc, and the output. Because the sensor fire continuously and don't need any clocking to initiate a reading, it is easy to interface with any microcontroller. For the seeeduino, the wire convert the 3-wire to 4-wire, to compatible with the twig interface of Grove.