THIS IS A REFURBISHED - TESTED TO WORK - APC BACK-UPS ES 550.  The price includes a 12 Volt 8 Amp Hour SEALED LEAD ACID Battery.

Protection of electronics, data, and computer software in the home and at the office is critical when the potential for danger approaches from an electrical storm, a power surge, blackouts, and brownouts. American Power Conversion produces battery backup equipment with protection in mind by connecting to an uninterruptible power supply. The APC Back-UPS ES 8 Outlet 550VA 120V provides battery backup when power is lost and acts as a surge protector when power resumes or during voltage spikes within an electrical current. Without a UPS unit, when utility power is lost while sleeping, the power failure can cause a disruption to workplace performance if the backup batteries in the electric alarm clock also fail or do not exist. In this type of situation, the alarm clock may not signal the correct time to rise from sleep, resulting in a late start for work. The APC Back-UPS ES 8 Outlet 550VA 120V provides surge protection through eight outlets, regardless of whether the UPS unit is turned on or off, and battery backup through four outlets when turned on. Connecting a single-line fax machine, modem, or telephone to the data line output will also protect these communication devices from a power surge. For maximum performance, charge the UPS unit for a minimum of 16 hours. The output power capacity and configurable power for the APC Back-UPS ES 8 Outlet 550VA 120V is 330 watts. The nominal output voltage is 120 volts. APC includes a PowerChute Personal Edition software CD as part of the accessories. In case of a long-term power emergency, this software can automatically save files and shut down the computer’s operating system. Accessories also include a USB cable that connects from the data port of the APC Back-UPS ES 8 Outlet 550VA 120V to a computer’s USB port. The APC Back-UPS ES 8 Outlet 550VA 120V gives audible and visual cues regarding its status so anyone who monitors the electronics within a building will be able to react timely to any alarms. When turning the switch from its off position to on, a short beep will be heard, and the LED light indicating the power is on will promote confidence knowing that electronics connected to the UPS unit are ready to be protected. A low battery warning will alert with a rapid, continuous beeping while the same LED light flashes. When the battery needs to be replaced, the audible signal will be a constant tone, and the “Replace Battery” LED light and “Power On” LED light will alternate flashing. If the battery experiences an overload to its available capacity, an audible constant tone will be heard until the UPS unit is turned off. When the battery power is exhausted and the UPS unit is in sleep mode, the audio signal will beep every four seconds until either the power is restored by the utility provider, or the UPS, the unit is turned off. Should a situation occur that involves faulty building wiring, the Building Wiring Faulty LED light will be lit in red. With the APC Back-UPS ES 8 Outlet 550VA 120V, there is no longer a need to walk throughout the house unplugging the television, stereo, computer system, and a variety of other electrical equipment and computer accessories to ensure their protection.