Syllable D80 Noise Reduction mini Handsfree Wireless Bluetooth 4.0 Earbud/Headphone/Headset Earpiece for iPhone 5S / 5C / 5 / 4S / 4, Galaxy S4 / S3 / And All Smasung And Android Bluetooth Devices &uml;CGreen Output power30mW THD+N=1 Power levelCLASS II Bluetooth VersionBluetooth V3.0+HS Impedance16 OHMDriver: 8*4 mm environment friendly Black magnetic design, low frequency is more powerful Impedance16 OHM