Product Detail Standalone Power Conditioner with Battery Backup 865-Watt, 1500VA output capacity, Stepped approximation to a sinewave 12 NEMA 5-15R outlets 13.4 minute backup time at half-load (432.5 watts), 3.9 minutes at full load (865 watts) Maintenance-free sealed lead-acid battery with leakproof suspended electrolyte . The "APC 12-Outlet J-Type Power Conditioner with Battery Backup" is best product for you. We recommended APC 12-Outlet J-Type Power Conditioner with Battery Backup