Smart-UPS models have long been considered the benchmark for all network and server UPS's. Smart-UPS feature a 16-segment LED display, extended range automatic voltage regulation (AVR), and pure sine wave output on battery. Additional manageability options are available through the Smart-Slot interface, which is an internal slot for the installation of optional accessory cards. The extended run Smart-UPS XL has the capability to add external battery packs to scale runtime from minutes to hours typically needed for converged voice and data networks. The entry level Smart-UPS SC is an economical choice for small and medium businesses looking to protect small switches, networking devices and point-of-sale (POS) equipment.