Are there multiple versions of the sigma 2X TC?

I'm looking for a 2X TC for my 120-300mm, and I can't tell off of ebay pics if there are differing versions, or just different angles of shots. I've tried to look, but can't find really anything aside from the APO EX versions

anyone know?

APO EX DG is the latest and best as far as I know. I don't know if there are other versions but this is the one I use with my 120-300.
My TC actually beat 2 different copies of the Canon 2x III in sharpness. The Canon controls CA better and has a little better bokeh (which only comes out in certain situations; most of the time the background is very blurry anyway).
Both times I ended up selling the Canon 2x III and kept my Sigma.

thanks gabe...i almost bought a non DG version last night on ebay, just cause it was $120...i think i'll go for the DG though....i am wondering if i should think of swapping out my kenko 1.4X as well...we'll see i guess.