ES-U2 is a single directional force balance accelerometer designed for structural engineering monitoring, with the latest generation EpiSensor from Kinemetrics used as the internal sensor. The EpiSensor sensor can select the desired full-scale value within the range of ± 0.25g to ± 4g, and users can choose the appropriate full-scale value for seismic observation and recording near faults or various structures. The bandwidth of the sensor has been increased to DC-200Hz, which enables the study of higher frequency vibrations while maintaining a very important DC response. Users can choose from four output modes: ± 2.5V and ± 10V single ended output, ± 5V and ± 20V differential output. ± 2.5V single ended output is suitable for traditional seismic recording instruments from Keni Company; ± 10V single ended or ± 20V differential output is suitable for Kearney's Makalu 24 bit digital recorder and other popular 24 bit digital recorders in the current market.