Apple is getting ready for a big press event on Monday, and if you’re curious about what they’re about to announce, join the club.

So what is Apple announcing at this major event? The company has mysteriously titled the March 21 show “Let us loop you in,” with no information about what they’re about to announce and a simple invitation to add the event to your calendar. It is scheduled for 10 a.m. tomorrow (Pacific).

Apple is already expected to do a software keynote address in June at the Worldwide Developers Conference, and another event focused on the iPhone 7 in late summer or early fall, according to a Fortune report.

But this event will be held at its headquarters in Cupertino, Calif. That means it’s likely to be a crowd of press and enthusiastic Apple employees. The event will be streamed live.

But what is going to be announced? Rumors suggest that Apple CEO Tim Cook is going to unveil some new hardware and software. Some are speculating that it could be new watchbands for the Apple Watch, as well as a new 4-inch iPhone to be called the iPhone SE, 5SE, or 6C.

It’s also possible that Apple unveiled a new 9.7-inch-screen iPad Pro that would have the same display size as the iPad Air 2. There’s even the chance that some new Macs could be unveiled.

Then there could be the operating system itself that could be up for an update. Apple might roll out iOS9.3, which would have better security in the Notes app and a Night Shift feature that makes it easier to read the phone at night.