Each 28 FT long refill, Compatible with Your Standard, Plus,XL+, Save your money, especially for cat lovers. NOTE: Including a Non-original cartridge The refills use the best material, and each refill is made of 7 layers film The refill bags are easy to assemble, please follow the manual in the package. Easy to assemble, simply pull out a bit of film, push it through the center of the cartridge and tie a knot at the bottom. Then, open the lid and funnel of the pail, place the cartridge on top, and push the refill all the way. Simple installation can save you a lot of time. Package: 6 pack of refills, 1 user manual and a Non-original cartridge are included