I think you're right, it doesn't need one. Come to think of it I seem to recall that same notched look on my old MTB. There are only two parts to it. One big old chunk that has the spindles and a threaded side, and another little piece that threads in. I have no clue what it all is, came off probably a 2004-2005 Specialized Dolce. Unless they kept the silver bar tape on the bike in later years, then it could be newer. It's a Specialized crank set, that's about all I know. Was part of my $115 ebay score for the full component set, except brakes *sniffle*