CyberPower’s CP900AVR has a fairly easy-to-use interface with just two buttons (electric power on/off and mute) and four indicator lights (showing if the device is turned on, when the battery backup kicks in, when AVR is activated, and when there’s a power overload) over the entrance of your unit. Image: https://the-party-setter15825.webdesign96.com/36749989/the-2-minute-rule-for-battery-ups-450-apc