[projectRDM]

There's a million pics and threads on this. Creating one more because you fail at researching is just pathetic.

For the record since the responses above aren't much better:

90-92 are all aluminum
93-96 are iron
Only the 1990 NA models are 26mm, all the rest are 30mm

And there's always (gasp) a ruler. Yes, a ruler. They've been making them for a few years now I hear.