The MAXBOTIX XL-MAXSONAR-EZ4 MB1240 is a proximity senser that is part of the Pololu line of products. It is a small, lightweight, and inexpensive ultrasonic rangefinder which can measure distances of up to 7m with 1mm resolution. This device is used in a wide range of applications, including robotics, autonomous vehicles, edge-detection, object detection/avoidance, and more. It features a wide range of features, such as a low power MCU with a sleep mode, wide supply voltage range with an operating temperature range of -30 to +75°C, adaptive background suppression and near-unlimited range readings. It also has the ability to output an analog voltage proportional to the range reading and can be interfaced directly to the analog input of a microcontroller.