APC Easy UPS On-Line SRV 6000VA RM 230V with Extended Runtime Battery Pack, Rail Kit (SRV6KRILRK) - Max Configurable Power (Watts): 6.0kWatts / 6.0kVA, Input frequency: 40 - 70 Hz Auto sensing, Output Frequency (sync to mains): 50/60 Hz +/- 3 Hz Sync to mains, Load Crest Factor: 3 : 1, Bypass: Internal bypass (automatic and manual), Interface Port(s): DB-9 RS-232, Intelligent Smart Slot, USB, Expected Battery Life: 3 - 5 years