The Nina Ottosson by Outward Hound MultiPuzzle level 4 dog game will keep your dog entertained for hours as they use their natural hunting skills to seek out the hidden treats! Your pups’ favorite treats can be easily hidden in either the outer or central compartments by sliding the puzzle pieces. This puzzle is ideal for dogs who have already mastered levels 1-3 of the Nina Ottosson puzzle line. Made from tough non-removable plastic parts and food safe materials that are BPA, PVC, and phthalate-free. Hand Wash with soap and water to clean.