This, for us and Ruby was a waste of money. I had been after one of these things for her to gnaw on and finally got hold of one. They are not cheap.
However, within half an hour, she had managed to nibble off three small marble sized chunks and eaten them. Also, her front paws, where she held onto it, got stained dark brown. It may well have gone onto to stain our carpets and furniture had she been allowed on it.
All in all, not brilliant and it is now in the bin.