APC Smart-UPS RT is a family of high-density, performance UPSs for voice and data networks, medical labs, and light industrial applications. Featuring double conversion on-line topology, the Smart-UPS RT protects your data by supplying reliable, network-grade power. An unlimited number of matching battery packs can be added to comply with aggressive runtime demands of "always on" business-critical systems. Rack-optimized models are an ideal choice for space constrained environments. Customers looking for extremely tight voltage and frequency regulation, internal bypass, and input power factor correction will find them in the Smart-UPS RT.