850VA APC Security Battery - 50 VA / 450 W backup battery power supply

Automatic self-test - Periodic battery self-test ensures early detection of a battery that needs to be replaced. Disconnected battery notification - Warns when a battery is not available to provide backup power. Simple battery replacement - Increases UPS availability by allowing quick, easy battery replacement. Hot-swappable batteries - Ensures clean, uninterrupted power to protected equipment while batteries are being replaced Battery failure notification - Provides early-warning fault analysis on batteries enabling timely preventive maintenance Adjustable voltage sensitivity - Provides the ability to adapt the UPS for optimal performance in specific power environments or generator applications. Audible alarms - Provides notification of changing utility power and UPS power conditions Cold-start capable - Provides temporary battery power when the utility power is out. Building Wiring Fault Indicator - This LED informs users of potentially dangerous wiring problems in the wall circuit. Transformer Block Spacing - Connect bulky transformer block plugs without covering up other outlets.