The Bone of A Thousand Chomps is a legendary bone that's been through the Pound Puppies units for many years. They say that a dog can chew on it and it'll never, ever splinter.
Big Chip gave Squirt what appeared to be the Bone, but it was later revealed to be a fake. Squirt found the real deal after switching places with Cuddlesworth, and gave it to Shakes the coyote in order to give the Pound Puppies safe passage through a "no dog zone."