"This storage container extension kit allows you to add 3 1/2 feet to your existing West Model 1260 or 1271 storage container to expand your storage capacity. Like the regular container, the extension is made of corrosion-resistant galvanized steel that will last for decades and will not need maintenance. You can keep adding kits until you reach your desired length. Outer Material Galvanized steel, Center Height ft., in. 6, 6, Dimensions L x W ft. 6 3/4 x 3 1/2, Style Modular, Frame Material Galvanized steel, Color Galvanized steel, Storage Volume cu. ft. 135, Frame Thickness in. 18- and 24-gauge. Extends length of West Model 1260 or 1271 Item# 24758 storage container by 3 1/2 feet Kit contains everything required to assemble and attach the addition The rear of your existing container becomes the rear of the expanded container"