This cover is good quality, made of a strong and hard-wearing material with a waterproof backing. It has adjustable straps which go round the headrests to keep the back in place; there are velcro-edged holes for the rear seat belt fasteners so that the seat belts hold the cover in place.
Drawbacks are: it was not quite wide enough for my Volvo S60 seat so that the ends rucks up when my small dogs jump in: and because the seat belts hold it in place they tend to get muddy when the wet dogs lean against them. However, if you use a dog harness you do need the belts to be accessible.
Having said that, the cover is easy to fit and remove and (apart from the width in my case) does a good job in protecting the seat from mud and wet.