Capable backup system with tubular batteries lead acid 2pcs and inverter charger 900va/12volts,it charges the batteries using electricity and if power goes off automatically the inverter converts from solar to electricity and no need to change your wiring,same wiring can work,if power comes back then the inverter starts charging the batteries,this system can hold gadgets of 800w at yr household and it can last longer without discharging,it is affordable backup system and it easy to be transported and to use, warranty 2yrs and 8yrs durability