Simple car seat protection replacing my towelrs

We are using towels to protect the bottom of our car seats.This doesn't look great and they move and when getting in and out of the car. But they do a great job protecting the bottom seat from any stains such as coffee etc; and they are washable. Looking around on the internet there seems to be only expensive complete car covers from custom to universal. Then there are ones for dogs. All we look for is a simple washable cover fitting at the bottom part of the car seat. Any ideas?

 

Actually I just found this one on Amazon. This is also great when getting into the car after a workout.

Does anyone have experience with this?