I found this adapter and I am quite interested in knowing what its for?

I found this adapter and I am quite interested in knowing what its for? It is quite short. One end is a USB Male. The other end is a 4 pin mini jack connector. I just want to know what its for.

Does this device have a serial number or part number?

No there are no identifying marks. I will post a photo tonight. It was not a custom cable. It looks like samsung made