Lifetime 60065 Raised Garden Bed, 4 by 4 Feet, 1 Bed This 4 ft by 4 ft garden bed is constructed of high density polyethylene; will not rot, chip, crack, or peel Easy do it yourself assembly requires no tools; full garden set up takes less than one hour Designed to absorb and retain the needed soil warmth for root development Walls are 9 inches high and two can be stacked to create 18 inch high box; can also be used as a child's sandbox Stylish simulated wood design; backed by a 5-year manufacturer's warranty