We hear our customer's feedback and improved the design of the product. Now the refill will never fall through the pail. Don't be fooled by the shape. Even it's round, it fits all Litter Genie and Litter Genie Plus pail system with our new design. There is a square outer rim that can secure itself on the pail. Each refill cartridge offers 14ft long bags which lasts up to 8 weeks for 1 cat. Your saving will add up, especially when you have more than 1 fur babies. ChoiceRefill litter pail refill is best alternative for cat lovers. Click Add to Cart to start saving.