Hi all! I would like to share my accumulated knowledge of Specialized’s M2 (Metal Matrix) frame lineup from 1991 to 2000. I will also include a serial registry here to help me (and others) better understand date and color differences between years and trims that may not be entirely obvious. The serial number format I will list below. The M2 frames are relatively common, but there were many differences over the 10-year production run, and I would like to help others ID their M2 bikes more easily, as it is not always obvious when referencing the available catalogs.