Simply place a treat in the Giggle Peek-A-Treat Ball and challenge dogs to get it out. Provides a great way to ease boredom, alleviate stress, and keep dogs mentally stimulated and challenged. Unique design features a transparent window in the center to give dogs a tantalizing view of the treats. Two air vents inside emit hilarious giggle sounds whenver rolled or shaken. Adjustable opening allows for different sized treats and can be increased or decreased in size with a simple twist to make it easier or harder for dogs. The 5 1/2" toy is made of durable, not-toxic plastic with a colorful bone design.