hello friends, im in need of help with my pool.

hello everybody im new to the forum, im very glad that i found this page b/c im in need of help with my pool. I have these two inlets on my pool wall that do not seem to be connected to anything. Now i was wondering what those ports were, they are not jets, my pool is kind of old so it only has 2 jets. One on the shallow end and another one on the deep end. Now these 2 ports are screw on ports it seems like you can screw something to them. Thanks for the help, I really appreciate it.