I have a security access panel in a closet. Behind the wall is an attic. Through a 1.5in conduit, I have about 3 CAT5e cables running through from the attic through the access panel. Is there a way to seal or terminate the conduit? Right now I just have some masking tape around it, but would like to properly close it or reduce the air gap. I plan to run 2 more wires down the road so I don't want to permanently close it. Thought about duct seal, but ideal if there is a more flexible solution to open and close the conduit.