Refill for Litter Genie Disposal System by Fresh Need 50% more bags in each refill cartridge due to patent design. If you have more than 1 cat, you will be surprised on how much you will be saving. Each refill lasts up to 12 weeks, that is 3 months for 1 cat, and 3 refills last up to 9 months! 7-layer bags hold the odor tightly inside; easy to install, clean; More bags in the refills means more environment friendly; you will throw away less cartridge. No risk to try. 100% compatible with Litter Genie and Litter Genie Plus system, or we refund all your money