The S4K2U1500-C is a four-outlet 1,350-W single-phase on-line double conversion uninterruptible power system including internal batteries. Rack- or tower-configurable, the SolaHD S4KC UPS protects equipment from power disturbances due to blackouts, brownouts, sags, surges or noise interference. Optional, matching external battery cabinets, also in a 3.5-inch size, offer extended runtime. The LED display indicates battery capacity, percentage of UPS load, battery operation, bypass operation and UPS fault condition.