Lightning and Surge Protection Protection from surges, spikes and even lightning is guaranteed! Resettable circuit breaker Instead of a hard to find fuse, there is a push-button circuit breaker for easy recovery from an overload or short circuit. Audible alarms Proactively notifies you of changing UPS and utility power conditions. Automatic self-test Periodic battery self-test ensures early detection of a battery that needs to be replaced. Transformer Block Spacing Designed to allow the use of up to two transformer block plugs without blocking access to other receptacles.