Yep, that's your oil pressure switch. Whatever you do, DO NOT buy one from O'Reilly's. It will continue to leak. I replaced mine, and now it leaks even worse. Replaced a couple of hours ago with OEM switch... same result
. The tech at the dealership said to use pipe dope and not tape, and it is a gradual thread. If it isn't leaking too bad I would just leave it be or you may be in the same boat as me. I don't want to over tighten it, but I'm running out of ideas at this point.