With a scaleable, modular and redundant design, the PW9170+ 9kVA Scalable to 18kVA UPS provides advanced backup power and power quality management and offers the highest level of power protection and power quality of any Rackmount UPS power supply in the 9kVA to 18kVA range.PW9170+ 9kVA Scalable to 18kVA UPS delivers ideal power management for server farms, networks, telecommunications, Internet service providers and other mission-critical applications for the best UPS power protection against all nine common power quality problems.