Steel M series mono posts are designed for permanent support during new home construction and can be easily installed by 1 person in less than 15 minutes. M series mono posts are fully assembled, have no loose parts, and are coated with corrosion-resistant primer. 3-inch outside diameter, 11-gauge carbon steel tubing. M series mono posts have a 4-1/4-inch x 7-1/2-inch x 3-gauge welded plate on 1 end and a 4-inch x 5-1/2-inch x 3-gauge swivel plate on the adjustable end. Each column has a 4-inch adjustment range.