When failure is not an option, the Premium Online Series UPS Backup Power Systems provide the cleanest power for mission critical, sensitive, and high-end systems. A completely isolated pure sine wave output provides perfect power free from noise and distortion for optimal system performance while the double conversion topology guarantees maximum system uptime. Front accessible batteries and remote IP management simplify maintenance and put you in control. The Premium Online Series UPS Backup Power Systems have a wide range of capacities, safeguarding any application. This expansion battery pack provides additional run time for Premium Online UPS models UPS-OL2200R and UPS-OL3000R Daisy-chain up to 10 battery expansion packs for longest runtime available in this form factor This unit requires two (2) UPS-OLRBP-2 replacement battery packs