I only use it to get carts and wheeled carts in when they are full of heavy objects. There is a lip on the outside of my front door frame. The edge sticks out about 4 inches and rises above the ground almost as high as the tallest part of this ramp. I don't know if it moves backwards during use as I have it on the wall under the door frame. Maybe a little wider. It's not wide enough to just go up and down without carefully aligning the wheels with what you're using it for, unless it's a standard-width cart.