APC Symmetra RM 4kVA Scalable to 6kVA N+1 220-240V (SYH4K6RMI) - Capacity: Output Voltages 220, 240, Output 4.2kWatts / 6.0kVA, Output Frequency (sync to mains) 47 - 53Hz, Input Frequency 50/60 Hz +/- 5 Hz Auto-sensing, Battery Type: Lead-Acid Battery, Included Battery Modules x 2, Connectivity: DB-9 RS-232, RJ-45 10/100 Base-T, Emergency Power Off (EPO), Waveform Type: Sine Wave