Yes. This one already has the 50mm tube installed when you purchase it. No need to buy a 50mm tube.
:up
That's interesting, I measured it as best I could and it shows that it's 55mm, I think. Or about 2 & 1/8" in US measurements. As best as I can tell. I found a pipe that is 2" around on the outside and it slips into the motor tube very tightly. I measured around it with a tailors tape measure and it reads 17cm around and google tells me that's about 55mm.
What I was looking for is a tube that it is about 2" around on the outside so that I could adapt it easier. I've been trolling ebay for parts to adapt the motor to my dish but to be totally honest, I have no clue what I'm doing, at all. Not even a little bit.