My wife is a slim woman and her new Chevy Blazer was christened with bird droppings and tree sap in our driveway - so not cool. We cleaned it up and she wanted a blanket - I doubt it would be needed but she puts it on when she gets home and keeps it closed. While I will help if asked, she basically steps on it herself. Is it waterproof? Who knows. This is by car, last time I checked it was possible to drive in the rain (without a cover of course). It keeps biological matter from getting ready - feces, sap, pollen (Virginia Spring comes with thick yellow pine pollen seeping in everywhere) and literally takes a minute to put on or take off. It has ratchet straps front and back and we've weathered several thunderstorms in high winds with no issues.