With its inset panels and classic design, the Fairfield 36" x 11" x 10.8" Rectangle White Self-Watering Polyethylene Window Box Planter is a timeless choice that will never go out of style. We use 100% high-grade Polyethylene resin in the manufacturing process - making our products durable, lightweight and highly shock resistant. Double-wall design makes these Fairfield Window Boxes sturdy, and provides the roots and potting mix with adequate insulation from surrounding weather conditions. These Polyethylene window boxes also have a built-in water reservoir.