Looking for info on oceanic plus series 4 skimmer.

[Damo_Na]

I recently came across this skimmer packed away from my last move. It's brand new but doesn't have any of the paperwork with it. It's a sump style skimmer and does have a pump. My question is this. On the main body of the skimmer, there is approximately a 3/4" hole that has nothing attached to it. Is there supposed to be anything? Or is it as simple as setting the skimmer in the sump, and plugging it in? I will provide pictures when I get home. Thought maybe someone might have had experience with this model.

 

[Damo_Na]

Ok, I just noticed the threads in the hole. I guess I'll turn the lights on before I'm looking at unfamiliar equipment from now on. Is it just a return pipe that goes in there? A short 90°?