This is the GPS antenna that came on 2000 and 2001 ML's.  If you have a 98 or 99, your ML is probably not wired for this.  I have a 1999 ML430 and while I attached this to mine, there were no wires to attach it to, so it's just for looks.  The COMAND stereos did not come out until 2000.  Good condition BUT THE COVER IS NOT INCLUDED..SEE PHOTOS...YOU'LL NEED TO USE THE ONE FROM YOUR CURRENT ANTENNA, ASSUMING IT'S THIS STYLE.