If you want to transport your dog on the backseat without using any box, you must fasten the dog with a seat belt. Beside the different possibilities of using belts, there is also the option of covering backseats with blankets and thus protecting the car against scratches and dirt.
The following questions will help you find the right belts and covers:
How can I protect my rear bench against scratches and dirt?
Do I want to enlarge the lying surface on my rear bench?
Do I prefer quick fastening?
Shall the blanket cover the entire backseat?
Shall the cover also have high side parts in order to protect the car?
Which loads must the product stand?
Can I also use the belt as harness?
Can I still take another person despite of the blanket?
Is the cover easy to maintain? Maybe even washable?