This system was designed for vertical pulling. The 50 mm (2'') square tubing fits on the tree/pole mount (PCA-1263). It is designed so the rope goes through the pulley and then straight up. It offers a solid support and is ideal for pulling electrical cables through conduits or lifting equipment. It also fits on the square tubing (PCA-1267) or adaptor for Heck-Pack (PCA-1265) when using a vehicle as an anchor point.