Works with Lumia 820 and Lumia 830

I ordered two of the straps - one for my wife and one for me. On the whole, do the straps, which they should. They are secure, yet comfortable for both my wife and me. Why 1 star deduction? The units have exactly the same Bleutooth identifier. As we walk together as a rule, it is sometimes difficult, when pairing with your phone select the correct (ie, the "own") device in order not to collect the data of the partner.
As the belts do not have a manual switch, but to me turn upon contact of the skin itself on and off again after a while after loss of contact, it only helps, disciplined, one after another only to put the belt and to perform pairing before / the Second invests his belt.
If someone has a tip on how you can change the Blueteooth designation * in the transmitter itself *, I would be extremely grateful.