1Compatible Model: This attic ladder hinge arm kit has strong compatibility, suitable for Werner Mk 5, WU2210, W2208, W2210. Only applicable to models produced after February 2010. 2Replacement Parts: These accessories allow you to replace only the hinge arm instead of the entire attic ladder, which greatly saves you time and cost, improves durability and work accuracy. 3Upgraded Design: These attic ladder hinge arms adopt electrophoretic coating technology, and the three layer galvanizing process ensures excellent wear resistance and erosion resistance. 4Easy Installation: This kit includes 2 hinge balance arms, 8 screws, and 4 washers, making it easy to install, convenient for you to replace old or damaged attic ladder accessories at any time. 5Convenient to Use: With a reasonable design, these hinge arms have accurate openings, improving reliable installation and strong load bearing capacity, allowing you to use them with confidence.