The Nina Ottosson by Outward Hound Dog Worker puzzle dog toy is a challenging level 3 puzzle game that will keep your dog busy for hours as they use their instincts to hunt for hidden treats. This advanced interactive dog puzzle game has 3 steps that your dog will need to learn in order to get to the tasty rewards: swivel the flippers, scoot the blocks, and spin the center wheel. Hidden compartments are under the flippers and under the center wheel. Made with no removable pieces from a BPA, PVC, and phthalate-free composite material. Clean with warm water and soap.