my collie bitch absolutely adores her Kong -- this is a had red (tho I believe dogs do not see colour?) ball designed NOT to be [picked up by the breed for which you purchase the appropriate size of Kong.
I bought this ball while she was still a young dog so it should have been impossible for her to grasp it within her jaws -- but she discovered a notch into which she could insert the very tip of a canine tooth, then grasp the ball (albeit tenuously) and run about delightedly with it in her mouth- if only just.
I always intended to write to the manufacturers to complain -- -
When not grasping this ball in her teeth she loves to play football, dribbling and nosing the ball till it gets stuck somewhere -- then she has a particular 'King' bark till someone comes to release the ball from wherever it is stuck.
My partner usually gets fed up and hides the Kong in somewhere inaccessible, which is fine until collie-dog finds or notices it, which could be minutes or weeks later- - then 'the bark' starts till someone comes and releases the kong!