Join the massive number of pet lovers that have been buying Kyjen's Puzzle Toys for the last 10 years. They work in reverse of regular puzzles; dogs take toys out, you put them back in. Their original puzzle toy line was created to challenge and develop your dog's intelligence and problem solving skills. The puzzles exercise a dog's natural instinct to search, stalk and capture its prey, as well as strengthening eye-paw coordination skills. Toy inserts can be replaced over and over again for endless entertainment and fun!