2014 Spy Covert Wireless Mini Invisible Earpiece + Bluetooth Induction Pen All advantanges are absorbed of bluetooth pen and enhanced secret communication function. More important, it solved the problem of short transmission distance. You can hear clearly in earpiece and whisper with partner by the new inductive bluetooth pen. The ultra compact designed bluetooth pen is build bluetooth module, hearing coil and rechargeable battery into small pen. No one will find this inductive bluetooth pen is build-in transmitter for earpiece unless studied it very carefully. The bluetooth module offers connection with mobile phone within 10 meters. Distance from bluetooth to earpiece is 30cm. The alternating current from bluetooth module flows throught inductive coil. The coil creates a magnetic field and drive receiving coil inside an earpiece within magnetic field. Package includes: 1 pc x Pen + 1 pc x Earpiece + 2 pcs x Battery. MY ADVISE: DON'T GET FROM SELLERS IN CHINA DUE TO PROBLEMS WITH RETURNS!!!