CyberPower’s CP900AVR has an uncomplicated-to-use interface with just two buttons (energy on/off and mute) and four indicator lights (demonstrating when the unit is turned on, once the battery backup kicks in, when AVR is activated, and when there’s a power overload) within the front from the device. Photo: Michael Hession https://andrelnnmk.bloggazza.com/35278915/fascination-about-battery-ups-long-wp5-12-12v-5ah