The Gnawt-a-Rock™ is a durable toy inspired by natural volcanic obsidian formed by rapidly cooling lava from Pacific Northwest volcanoes. Made with natural latex rubber and a faceted surface with an irregular shape, this interactive toy keeps your dog engaged, whether chasing after its erratic bounce or nosing it around as an interactive slow feeder puzzle toy to stimulate their mind. Our toys are designed to be interactive – it's just more fun that way. While our toys suit a range of play styles, dogs can be crafty and determined chewers, so supervised play is recommended. If any part of the toy becomes loose or detached, take the toy away and discard. Holds Treats Holds and dispenses treats or kibble for slow feeding and mental enrichment Erratic Bounce Erratic bounce for engaging fetch Easy to Clean Natural latex rubber is top rack dishwasher safe FDA Approved Food Contact Safe Materials