Sometimes the squirrels are on the right side of the car. Sometimes they're on the left. What's a dog to do? The Auto Zip Line is, you guessed it, the world's shortest dog run. Mountable between opposing seat belts, above-door handles, or any other fixed point in your car or otherwise, it keeps your dog in the backseat (where you need them to be) but free to roam, all while protecting them from their own worst impulses.