I have a wide array of battery chargers for various devices including cell phones and blue tooth ear pieces. Do anyone know if these can be interchanged? Do you have to use the charger that specifically came with your device even if they have the same type of plug? I have a Motorola ear piece and the back says "input 100-240v - 50/60 hz, and my Blackberry says they same thing. For outbput the motorola says 5v -- 550mA and the Blackberry says 5vc.c. 0,75A for output.