OK,
The serial adaptor that im using is the ES-U-1001-R100 made by
EasySync USA
It is the second and third one on the list on that page. One has a 10cm cord and the other has a 100cm cord.
This one works right on my mac which I love!!
And!! Its only $24.98!
I have bought many serial adaptors to find one I like, And I like this one the best.
-Adam