The external footing is basically a piece of aluminum shaft that fits nice and tight forming a sleeve on the end of the arrow flush with the insert. It helps strengthen the end of the shaft as well as add a little weight in the front. Another benefit…the location of the external footing’s weight is better than having the same weight farther up the shaft behind the insert. You have the weight in your arrow…. but FOC is not as good the farther away from the point you put the weight.