I have to park outside and I live far north. We had about 225 inches of snow last winter and it was cold enough to stay. I don't drive the car often, so it was sometimes difficult for me to lift the car from a spot after a week or more when snow and ice had accumulated around it. These guys are doing a good job. I'm front-wheel drive so I put one under each front tire, big lugs down and small lugs up and out. Two or three times when I couldn't move (the wheels were spinning, they weren't going anywhere), I got rid of those rugs myself.