This universal adapter connects wood fence rails to 2", 2-1/2", and 3" metal fence posts. It is made of a flat base plate featuring screw holes in each corner, allowing it to be securely attached to your wood rail. The clamp's two pieces, designed to hold the metal post, are held by screws and nuts. After fitting the clamp around your post, tighten the nuts to secure everything in place. When constructing a wood fence with metal posts, you must have an adapter, as the two materials are not intrinsically connectable.