I spoke to Irwin about these years ago (I think at the 2004 Internats) where he gave me a few of the lower units. If I remember correctly, they were made from a fiber filled material like Carl mentioned. I ran it for a little while and it worked out just fine. The guy who actually made them was named Richard (cant remember his last name) which is where the name REK lower unit comes from, his initials. The injection work was very good, and it inlcuded an encased brass sleeve for the flex if I remember correctly. I never had any issues with mine. I remember having to sharpen the skeg with a razor blade...