Our molded plastic planters are made from high-grade polyethylene, double wall design * Sub-irrigation water system, encourages root growth * Inside dimensions are 12.25"l x 12.25"w x 11"d * Soil capacity is approximately 5 gallons (19 litres), water capacity is approximately is 3.7 gallons (14 litres) * 15-year limited warranty. for more information please call us toll free at 866-363-8834.