The ryobi that I have came out of a Troy Bilt TB70SS weed eater. It has the four transfer ports and also has two rings. I just wanted to post this so maybe when yard selling or scronging, a person would know that this trimmer has the desired engine.

I also posted this just hoping that maybe somebody would chime in and revive this thread. I have read it almost two times and have learned so much from it. There was some childish posts made but they are easy enough to ignore. Anyway, thanks for the vast majority of the posts from the majority of the posters for a gold mine of information.

Bill