ALFAPET'S new Flat-Bottom Sifting litter box liners, utilizes our patented sifting technology with our newly patented flat-bottom technology to create the first ever flat-bottom sifter. By combining these features, cat owners are able to swiftly sift their litter box without dealing with messy folds and/or trapped waste. These liners provide a better fit thus reducing the mess and time to clean the cats' litter box. The quick sifting action helps eliminate the need to scoop, while the drawstring helps secure the clumps that remain in the bag. Simply place the solid flat-bottom liner in the litter box first then add the sifting liners and then litter. Once your cat has used its littter box and it is time to clean it: you simply lift up the top sifting liner and the good litter will swiftly sift back into your litter box leaving the clumps in the bag for easy disposal. These liners are a "Simple - Safe - Sanitary" way of changing the litter box!