What is this thing on the back of my active2?

[user2hnbSGSOc8]

Hi there,

I have looked everywhere but I can't seem to find any answers. What is the little oblong circle above the heart rate monitor on the galaxy watch active2? Here's a photo

[Anonymous · Accepted solution]

Hey their. This is a testing port. It is not used by end consumer you can ignore it.

[userlvYG6P5QFA]

I was wondering the same thing, it was driving me bonkers.  Couldn't find any documentation on this.  Don't know if you're like me but I just had to know.  Thought sim card slot, expandable memory, charging port.  I figured it was some kind of port, it looks like a cover/door that can be removed.