IF YOU ARE A PG&E CUSTOMER, YOU NEED THIS. APC Back-UPS 500 provides battery backup and surge protection for computer and electronic components. When power quits, this device will power your computer and monitor for about 30 minutes, giving you time to save and shut down safely. Also protects your computer and electronics from electrical noise, spikes, cycles, lightening storms, and damaging power surges. Two backup plug sockets. Accessory surge protection socket. Input: 120V, 60Hz, 10A Output: 120V, 60Hz, 300W, 10A Backup battery has been replaced.