Tripp Lite's premium UPS replacement battery cartridges breathe new life into UPS systems suffering from expired or weak internal batteries. Each replacement battery cartridge is carefully screened and certified to meet or exceed original specifications and ships ready for installation. Reusable packaging holds expired batteries for recycling center delivery. See Tripp Lite's UPS replacement battery web page to confirm compatibility and quantity required. COMPATIBLE WITH TRIPP LITE MODELS SMART500RT1U, SMX500RT1U