APC Replacement Battery Cartridge #135 APCRBC135 Genuine APC RBC(TM) are tested and certified for compatibility to restore UPS performance to the original specifications. Batteries & Runtime Battery Volt-Amp-Hour Capacity 168 Battery Type Maintenance-free sealed Lead-Acid battery with suspended electrolyte : leakproof Battery mounting Stand alone battery stack Expected Battery Life (years) 3 - 5 Battery Placement Internal Battery RBC™ Quantity 1 Battery blocks per string 2