The Backup Power Source 1250 system is easy-to-use and delivers instant, automatic backup power in the event of a utility failure. Plug and play installation with simple color-coded battery hookup. U.S.A. Standby Unit: Yes, Running Watts: 1,250, Surge Watts: 2,500, Battery Type: 220Ah Maintenance free AGM batteries, Battery Qty.: 2, Rechargable Battery Bank: Yes, Alternative Power Collection: Works with grid power, solar panels or generators, Modified Sine Wave: Included, Solar Power Compatible: Yes, Dimensions L x W x H (in.): 18W x 18D x 25H Batteries receive a trickle charge when grid power is present If power fails, system automatically delivers AC power to essential loads, even if you are not around Ideal way to keep critical items like sump pumps, computers, office equipment and aquariums running Modified sine wave output power will work with sensitive electronics Versatile battery system works with grid power, solar panels or generators 18in.W x 18in.D x 25in.H