Dog hammocks prevent your dog from roaming in the car and distracting driver's attention, adn from falling on the floor. But for longer car journeys or trips at high speed, you should make sure to secure your pet with a safety belt additionally. Most hammocks do not have their own straps, but have openings in the back part through which a strap can be connected to the buckle of the car - but for this you should use a special dog harness and not simply attach the dog leash to the collar. These openings should have a hook and loop fastener to keep the car hammock waterproof