"The No-Dig Ground Anchor offers a faster, cleaner, and easier way to install your mail post. It's an ideal way to avoid digging a hole and mixing concrete, it truly is a time saver. Made of galvanized steel. Measures 3"" L x 3 1/2"" W x 27"" H. Includes mounting hardware. Requires one 4' x 4' wood post (not included). 1-year warranty."