When Superman 'walks' Krypto, how exactly does that work out? They both can break the sound barrier...so what happens when Krypto wants to chase a car? Suppose he has to get it. Certainly wouldn't want a super-charged puppy bum rushing the car...would be far worse that Cujo! Superman should probably keep Krypto on this 4 foot long Superman Symbols Dog Leash. We all know the 'Supers' can't get enough of that S crest, and this Superman Symbols Dog Leash is no exception. Why don't you take Kal-El's example and pick this puppy up for your puppy!