It is one that I inherited from someone at work. The cats owner could no longer take care of her. After trying it out at a relatives house, it didn't work. So the ladies at work(relatives that tried it), asked me if I would try her with my cat. Not really bad, but My first baby is just WAY to spoiled. Since the other cat also came from a one cat one owner house, she just isn't as happy as I know she could be. Just want everyone involved to be happy--especially the babies!