I just got this combination for my D4 and I really like it. Anyone else have this setup? If so, I wanted to know if you ended up using any of the rings that came with each peace. I, for the life of me could not get them on...so I just put the DK-17 inside the DK-19 and screwed it on and it fit like a glove. I was just worried about water getting in; but given the way it is on...I don't think I have to worry about it. So I hope I did it right...if not, please let me know.