The USB Crack Movement Recorder provides continuous recording of both movement in crack width and ambient temperature. The unit is configurable to measure at a pre-defined interval of 1 minute to 91 hours. The built in data logger stores readings for later download onto a PC. The unit is powered by a user-replaceable battery, which should last between six months and five years, depending on how the unit is configured and frequency of downloads. The measurements are stored in internal memory and are downloaded to a Windows PC using a USB cable (supplied). Monitoring in two dimensions using two units (normally horizontal and vertical) is explained in the manual. The unit is supplied with fixings, a USB cable and a link to download the latest version of the user guide and software.