The Circular Sand and Water Tray promotes sensory play and STEM concepts such as weight, buoyancy and water displacement. And the table's lid cqan double as a sand box! Children scoop, build and pour as they play, which improves fine motor skills and hand-eye coordination. The powder coated, tubular steel frame prevents rust. The tray is injection molded which creates uniformly thick plastic for strength. It will withstand being filled with water or sand without bending. The unique tray contains a higher island in the center that is surrounded by a spiral-shaped channel or roadway, stimulating curiosity and imaginative play. Includes a drainage hole, screw-in plug, plastic lid and non-slip plastic feet.