If I have two LG Tone HBS 700 Bluetooth headsets, will my android phone recognize both?

[AC Question]

The battery on my older Bluetooth is not as efficient as it once was. I want to buy a new, identical device that I can turn on when my older one runs out of battery. Will my phone see them as two different devices, or as one device that will just reconnect when I turn the fully charged new one on? I do not plan or need to use them both at the same time, I just need more than eight hours continuous Bluetooth connection. Thank you!