Our heavy-duty plastic benches are made of high-density polyethylene (HDPE) with UV inhibitors built into the product to prevent fading so they can be installed inside or outside. They are very durable, rugged, and long lasting and because they are made of plastic, they will not rust, corrodes or warp and will not crack even with freezing temperatures. Tops are 2 5/8 inches thick and can handle up to 35 lbs. per square ft. of space. Very easy to maintain, just hose them with water, has holes for easy drainage. They can be dis-assembled easily when not in use for storage and use them again for the next season.