ya they are sli compatible i, but i had just put the cards in and the system was not running anyway only the loop was running to check for leaks so i didnt get a chance to put the connector in at the time of this pic. I was going to use shorter tube but it didnt seem like it wouldnt seal well on the barbs (plus i was not aware of a standard in length)
EDIT:
looking at a 4" tube and trying to picture how it goes on the cards without kink?
EDIT EDIT:
i guess i could just reverse the flow in one of the block, prolly doesnt matter anyway. then i could have a small tube connecting them in the middle which is probably what you are talking about.