The 18-inch-high Galvanized Steel Raised Garden Bed is designed to be strong, long-lasting, and attractive, and it allows one control over both soil and drainage preferences. It's made of corrugated, 18-gauge galvanized steel and is available in these five sizes:2'x 2', 2'x 4', 4'x 4', 2'x 71/2', and 4'x 71/2'.