I use the cheap Walmart one - Special Kitty. Works as good as the more expensive ones. I've tried them all. I even bought a bag of outlandishly priced super-crystals - they won't even set foot in the box. It was never used. I tried the pearls. They worked the best for odor and cleaning, but the pearls stuck to their paws and I had little pee-filled pearls all over the house. Step on a few of them and out go the pearls and back comes the Special Kitty. Trust me, my 2 cats have the most functional digestive systems ever! That's why Roxy and Remi are constantly cleaning their tushes for them
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