Dogs love scent. Their sense of smell is 10,000 times more powerful than ours! As a Playology toy is chewed, the scent is released to keep dogs engaged - plus the smell lasts for at least 6 months! Durable for less aggressive chewers, designed to puncture without tearing Made with dog-safe materials. This toy is tested to meet ASTM guidelines for safety for children's toys and the CPSIA (Consumer Product Safety Improvement Act) standards for lead, phthalates and other toxins deemed hazardous. Treat free - Unfortunately, over 50% of U.S. dogs are overweight. Playology toys smell so engagingly delicious, you don't have to add food to make them interesting. After all, dogs shouldn't need food to play with a toy. They should play because they love it!