The bungee line runs inside the pole and out a hole. You simply pull it tight and attach it to the built-in jam cleat. The bungee allows the unit to give a little if you accidentally hit it, but it allows enough force to hold it down tight. I did wrap the deck bungees around the base to add more downward force only on the much rounded foredeck. On the aft deck where it was much flatter it worked better. The rubber base forms to the deck, but if the deck is really curved it may need a little more force, as I found it wobbled just a bit- not much. With the deck bungees wrapped around the base it was solid.