2. All Frames (the 2-3 rows of horizontal 2x4) are secured to the posts using 3'" long "Lifetime Warrantee" galvanized and painted screws. This takes almost 4 times the labor, and the screws cost 5 times the nails that others use, but it is where most fences fall apart in the future and is worth the time and cost. Most of the fence repair / replace projects I am called to, the most common cause of the fence falling apart is because the installer simply used the same 2" nails for shooting pickets to build the frames as well. This results in only 1/2" of securing....go figure???