These Soap Box Derby wheels "found me" while I was poking around looking for my next project. The stories they could tell! So many youngsters learned to "engineer", problem solve and live on the "dangerous side" as they crafted and cobbled together a speedy box on wheels. What fun to feel the wind in your hair in a gravity powered car! When I lined the wheels up on my floor to inspect and relish them, the rubber edges touched and turned. When I scooted them all together, they all turned, and that was it! The Wheels Have Spoken...they need to turn! My son and I made a backplate that would allow the wheels to hang on the wall and turn. Super easy to hang either horizontally or vertically.