Lessee if I can explain it: at the bottom center of the plate, about 1/4" or so from the edge, you drill a 1/4" hole. You take a 3/8" diameter piece of rebar about 6" long, and taper one end. That end gets stuck in the hole. THe plate sets verticaly, slightly leaning toward the shooter, with the rebar sticking out toward the shooter. On impact, with any movement of the plate, the tapered rebar workes out, and the plate falls. Light hits the plate tends to fall forward, heavy hits make it fall back. As long as you set the plate back in the same place, its the same for everybody.