The T4-600 24 in. – 3 1/2 in. x3 1/2 in. OZ-Post Anchor is a modified version of the standard T4-850 post anchor that is specifically designed for areas that have hard packed soil, asphalt, rocky, roots or driving into rotten posts. The T4-600’s fin length is 30% shorter and is 50% thicker compared to the T4-850 to increase penetration performance in these difficult installation areas. The T4-600 should only be used for a privacy fence when the soil conditions are firm enough to support the project. This post anchor is also great for installation of mailbox posts, birdhouses, picket fence or other lightweight projects. OZ-Post Anchors are the only post anchors industry tested to be the very best. OZCO’s OZ-Post post anchors are a better option to post hole diggers and pouring concrete footings, providing superior support for your project. OZ-Post products anchor your wood post with no digging, concrete or mess while keeping the bottom of posts safe from water and rot. These posts are made with hot-dipped, galvanized steel and for maximum longevity and suitability for contact with pressure treated lumber. Easily installs with a sledgehammer, manual driver or a jackhammer. Check out our instructions and videos for more information.