Everlasting Treats can also be inserted upside down or into the center cavity of the ball for more "The Everlasting Treat Ball can be filled with food, Every Flavor Treats or any snack your dog enjoys and then capped with one or two Everlasting Treats. Everlasting Treats can also be inserted upside down or into the center cavity of the ball for more challenging play. Dishwasher safe in the top rack for easy clean up. Completely free of latex, vinyl, and phthalates.