The Nina Ottosson by Outward Hound Challenge Slider is a fun way to challenge your dog's mind! This Level 3 Advanced dog puzzle is great for dogs who have mastered Level 2 dog puzzles. It keeps dogs busy with mentally stimulating treat challenges that activate your dog's senses and tap into their natural instincts to hunt and forage for food. As a result, our dog enrichment toys provide mental and physical exercise, help relieve stress, and reduce boredom for happier, healthier pups. Great for small, medium, and large dogs, the Challenge Slider requires dogs to complete a series of actions in order; this encourages dogs to tap into their mental skills and problem-solve right before your eyes! Watch your dog use their brain to sniff out the treats, then slide the tiles one at a time to reveal the hidden rewards! Since all dogs are unique, you can vary the level of difficulty of this dog food puzzle to meet your dog's problem-solving ability, with multiple ways to make it easier or harder for your pet. Moreover, this dog treat puzzle is easy to clean and made from food safe materials that are BPA, PVC, lead, and phthalate-free for your convenience and peace of mind.