Greenworks power washer and foam cannon question

I just purchased the greenworks 1600psi electric power washer. From what I am reading, the popular choice for a cannon is the MTM hydro cannon for $59.99. I have also read if you use this, there are some fittings that need changed. Does anyone have any input on the type of fitting that is needed to have this connect to the handle portion without using the extension piece? Thank you