Offline UPS 400-1500Va with Cheap price, good quality, low fault rate, Automatic Voltage Regulation (AVR) Function and CE Certificate Key features Optional function 1: Line Surge Protection: RJ11/RJ12/RJ45, 2:Communication Interface: RS232 3: Control mode: CPU controller 4: Function & Characteristic: 5: AVR,Overload and short circuit protection 6: Low battery alarm, LED status display 7: UPS Auto on when AC back, Night charging(optional) 8: Standby Function, Backup UPS Power 9: Built-in sealed lead acid maintenance free battery.