I purchased this product for my guinea pig cage that I built with my own grids. It was totally worth every cent. The instructions are very clear and easy and the product works exactly as it should. I have 3 cats and I was worried they would try to eat the piggy. Actually, while I was assembling the lid, my cat actually jumped in the piggy cage, but not to eat the piggy. He just liked the fleece! He curled up to go to sleep and was not terribly happy about having to get out! LOL! It is definitely sturdy enough to sustain even my Panther sized cats sitting on it, but they dont sit there anyway. You can always use a carabeaner to keep the lid down if you have pets that might try to nose the lid up.