I have a big fine thing with a kid on it. One little kitten. I'm changing the full thing twice weekly because of the giant bags in it. She rips them to shreds and it kind of loses the point that they are a bag! It's costing me s bomb. My friend was telling me about some expensive contraption which means she only empties once a month and she uses best clumping litter on top of it. I don't get on with the clumping she gets it everywhere but any idea what my friend is talking about? This is the slave with s £1200 cat tree btw so I do t think she's talking wilkos.