SaniSolution Smart Cartridge™ UNscented dispenses the exact amount of sanitizing solution needed to decontaminate Granules and Genie Bowl and to keep the CatGenie running properly. Made with same ingredients used by veterinarians to sterilize their exam and operating areas. One Cartridge lasts for 60 washings. CatGenie needs Smart Cartridge to run. Best to keep a supply on hand. Alerts you when SaniSolution is low. Cartridge is 4" x 7" x 1.5". 15 Fluid Ozs. Weighs 2 lbs. CAUTION: This green colored 60 wash Cartridge will ONLYwork in the original CatGenie 60 Model. The original CatGenie unit has blue colored buttons and the CatGenie 120 has orange colored buttons. Please note: The 120 Cartridge will NOT work in the CatGenie 60.