That is interesting, never thought of that! I suppose that they could be just riveted on also? I have not found the mudflaps useful in the least. I live off road ruts mud and stone etc on ruts they are always catching and sometimes the rears in part come away showing a weedy wood type screw that just seems blind no way to re-screw. in the mud it sprays everywhere anyway because they are not big enough wide or long and they are too stiff. Would prefer something like the old rally cars with long and wide but soft rubber held back with a bungee cord so that one can not run over them when reversing or could pull right back and out of the way. If I was specking a vehicle now, I would omit the mudflaps because they are totally useless and catch.