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 unit is turned on, when the battery backup kicks in, when AVR is activated, and when there’s a power overload) within the front of the device. Photo: https://thanrak62726.blogunteer.com/35254256/5-easy-facts-about-battery-ups-ย-ห-อไหนด-described