The Everlasting Fire Plug 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 for more challenging play. Dishwasher safe in the top rack for easy clean up. Completely free of latex, vinyl, and phthalates. Large (4.25″ diameter) recommended for dogs over 40 pounds If your dog is a strong chewer, we recommend selecting the larger size.