dog mental toy,dog intelligent toy,dog toy product size:30cm*20cm*2.7cm how to use: 1.hide the snacks in the cavities under the sliding lids or wings 2.teach your dog to move the lids or dial the rollers by paws or noise,to find food. 3.for the first time,you 'd better to demonstrate,your dog watched and learns,till it knows how to play packing: each in a clor box