This is yet another issue raised when lifting a TJ and now addressed by Nth Degree. With taller springs, and hence a lowered axle, the spring perches are shifted off center and the bumpstops don't line up anymore. Nth provides this upper spring-mount relocating plate, which again puts all the geometry right, keeps the springs from coil binding at full stuff, and allows the bumpstops to do their job as designed. Although you can't see it in this photo, the bumpstops are spaced down enough so that they actually do their job before the shocks bottom out and do it instead. This is a "must" if you do any fast, "Baja"-type driving.