they're floor stress bars (simple right? lol) if i'm not mistaken. There's a different one called a cross brace (standard on the e36 verts i believe) that bolts on under the chassis. its a simple bolt in and does alot better, but they cost more. Check out strictly german in braselton to get one cheaper than ordering from somewhere like bavarian autosport. e36 models were my thing for several years and i actually have a Reiger front lip for non-M models lying around somewhere if you might be interested.