Radar. In the steel mill and other big facilities that is a standard. I had a pull that the wire was 3 500mcm armored cable 1800 feet. At the end and at a thousand foot I had super tuggers setup. We stopped the pull pulled the rope back used a mares tail to go around the cable. Other than the one stop pulled it right in. This pull was on the side of a mill and the cable hang on messager wire. The conductor on the reel weighed in at 32,000 lbs. It was fun. Also the brackets were 60 ft in the air. Used a greenlee payoff machine to help get the reel turning.