Kit Cat SOYA CLUMP is 100% biodegradable soy-based cat litter with mild aroma. This unique product is made from the insoluble parts of a soybean which is found in soymilk production. Normally these insoluble parts are mainly disposed in a landfill, but Kit Cat innovates a second purpose for this wasted material to be used as cat litter, labeling us as Eco-Friendly.