We have the largest and we have the next to largest. The largest are black and the hardest, but the girls prefer the smaller sized colored ones. They are not little enough to swallow or anything, but the colored ones apparently are a little bit softer. Moonlight also loves her kong ball which we do play with in the back yard. It weighs a "ton" but you can throw it, and it has grooves that are good for her teeth. It's also red, so it's easy to find.
Nina
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