Original Plantronics Explorer 243 Universal Bluetooth Headset.  Compatible with all bluetooth enabled devices like cell phones, PDA's.  Digital signal processing (DSP) for Noise reduction.  Acoustic echo cancellation, discreet microphone placement reduces wind noise.  QuickPair Technology and Secure Simple (SSP) for easy pairing.  Call rejection, last num redial and voice dialing (if supported by phone).  Multi-function button to control various functions including answering & ending calls.  Volume controls fit either your left or right ear.  LED indicator shows headset status & connection status.