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 replacement battery pack is compatible with UPS-OL1500R model, and the left slot on the OLEBPR-2 expansion battery pack.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 replacement battery pack is compatible with UPS-OL1500R model, and the left slot on the OLEBPR-2 expansion battery pack.