Main Features: Bluetooth 4.0�� Adopt Bluetooth 4.0 technology， transmission distance is up to 10mBuilt-in MIC�� Built-in microphone supports answering / reject / end / transfer calls， last number redial， voice-command dial (if your phone supports this function) and hands-free talkingMultipoint Connection�� It can be connected with two Bluetooth devices at the same time， so you can enjoy the wonderful music with your lovers or friendsNFC Function�� Make sure the operation system of your phone is above Android 4.11 and with NFC functionFive Functional Keys�� MFB (power on / power off / play / pause)， volume +， volume -， backward and forward buttons Color: Black，White Wearing type : Ear Hook Function: Microphone，NFC connection，Answering Phone，Song Switching，Voice control，Bluetooth Connectivity : Wireless Connecting interface : Micro USB Application: Mobile phone，Sport Driver unit: 9mm Frequency response: 18-20000Hz Impedance: 32ohms��15 percent Sensitivity: 110 dB Microphone frequency: 20Hz - 20KHz Microphone impedance : 32ohm / typ Microphone dimension: 9mm (Diameter) Input Power: 5V / 0.5 - 1.0A (Charger output) Talk time: About 8 hours Music Time: About 6 hours Standby time: About 200 hours Charging time: About 2 hours Bluetooth: Yes Bluetooth version: V4.0 Powlev: CLASS II Bluetooth distance: W/O obstacles 10m Bluetooth chip: CSR4.0 Bluetooth chip sensitivity: -90dBm Bluetooth protocol: A2DP，AVRCP，HSP，HFP Bluetooth mode: Hands free Package weight: 0.099 kg Package size (L x W x H): 10.000 x 11.000 x 4.000 cm / 3.937 x 4.331 x 1.575 inches Package Contents: 1 x AH03D Bluetooth 4.0 Earphone， 1 x USB Cable， 4 x Spare Earplug， 2 x Earphone Cover，1 x English User Manual