Designed for use on gym floors. Boards have non-marring plastic composition, ball-bearing wheels. They come with a hole in the center for storage. For safety considerations, please limit weight on scooter boards to 150 lbs. Warning: use only under proper supervision. Protective clothing and equipment should be worn when using. Do not stand on unit, injury may occur if product is not used properly. Always check with Supervisor about proper usage. This product is manufactured in China.