Car hook/Purse Holder

Here is a purse holder hook thing that goes on right behind the seat of the car.
All you have to do is take the head rest out slide the holder over the head holder rails and just put the head holder back in place, the holder is probally going to be able to spin freely around when there is no weight on it, that is perfrectly normal, and there hasn't been any problmes with it moving a lot when the car is in motion or when bags or a purse is on it.