A clip to hold the bulging front panel in line. Fits both top and bottom if you really want to go nuts! !!! WARNING !!! This can scuff up the plastic panel material very easily. Do a thorough clean up of the pieces that slide over the panel and be careful installing/uninstalling. It fits pretty well and does what it's supposed to, but you'll probably need to do a little filing of the inside channels to make it fit flat & square.