CyberPower’s CP900AVR has a fairly easy-to-use interface with just two buttons (electrical power on/off and mute) and 4 indicator lights (showing once the device is turned on, when the battery backup kicks in, when AVR is activated, and when there’s a power overload) about the entrance of your device. Photo: https://thankrak04814.blogs-service.com/67232897/fascination-about-battery-ups