We just upgraded to the cat genie 120 from the 60. We had purchased the sidewalls for the old unit. The great thing is they work with the new one. They definitely have cut down on the amount of granules our cats "throw" out. One thing I have found useful is I purchased a small rechargeable hand-vac to vacuum up the granules so I can put them back in the litter box. I dump the contents of the vacuum out on a towel so I can take out any hair or unwanted debris. This also allows for longevity of your granules. Overall the sidewalls in my opinion are a must have. For only $20 it's worth it.