Mark they look like this


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Keep in mind, I use them to go under my 4ft steel ramps that hang on the back lip of the trailer when loading. The wood ramps make the angle less steep and allow loading cars with splitters. Depending on your car you could make the wood ramp like mine (only a couple of feet longer) and flip it over and it would work fine. You can get those metal ramp ends to go on the 2X12 at Tractor Supply. I think if you did it like below it would work.

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Put the ramp end on the top right (xxx), and move the bottom boards in a little so the top board hits the ground and you should have plenty of support. Maybe a little heavy, but that keeps people from stealing them!