I see it's kinda like vinyl but has very little sticky backing to it so as not to ooze and drip inside the case. I'm thinking it's mostly for airflow to make sure the air coming off the fans vents outside the case and not back in. That means the main slit between the fans and heatsink and the two screw holes need to be plugged for sure. I went to some stores today and asked around.

You would be amazed at the number of people that also have no idea what it is. And just mention the word computer lol and they go running. I really like the duck tape idea. My question is will it be too sticky and ooze as it heats up? Electrical tape seems like a disaster to me as I have used some on cables before and man what a mess it leaves. I found a place that sells duck tape sheets you can cut but that stuff is so flimsy. Was thinking about contact paper. Any thoughts about that? Good to hear it's not thermal as that saves mucho money when shopping around lol.

I have had mine apart since and it seems the tape just dries out where exposed I have no mess.