ADVANCED LEVEL DOG PUZZLE: Nina Ottosson's Dog Twister Level 3 Dog Puzzle is an advanced level game. It challenges your dog to learn a series of steps in order to solve the problem. It's a fun way to channel your pup's destructive or negative behaviors while stimulating them intellectually! SLIDE, PULL AND LOCK TO HIDE TREATS: Arrange treats in the compartments under the triangular blocks, then push the white plastic handles to lock the blocks. Your dog will have to successively pull on the handles to unlock the blocks and then move them to discover the treats! NON-REMOVABLE AND EASY-TO-CLEAN PARTS: the parts are not removable, to prevent your dog from getting chokes when playing. This game is very durable and will not deteriorate, becoming your dog's favorite treat puzzle day after day. BPA, PVC, PHTHALATES FREE: Nina Ottosson's Interactive Dog Treat Puzzles for Outward Hound take your pet's health into consideration. They are made from food grade materials that are safe for your dog. Easy clean up after each use with warm water and soap. BE CAREFUL: Even the strongest toys can sometimes get damaged. cause damage. Do not leave your pet near a toy unattended. If damaged, remove and replace.