V4.1+EDR Version: Transmission distance:10-15m for straight line and barrier-free Class2 Charging time:2hrs Talking time:7-8hrs Music time:6-8hrs Standby time:200hrs Frequency:2.402-2.480GHz Support Agreement: HSP/HFP/A2DP/AVRCP Sensitivity: <0.1%BERat-80dBm RF Output:-6dBm to 4dBm Input:5V/1A Battery:3.7V/100mAh rechargeable Li battery.</br>CONNECT TWO DEVICES: It can connect two devices at the same time when a device is disconnected another device can be connected automatically which is very smart and absolutely wireless stability. The earbuds that work with all smartphones tablets and music players.</br>SUPERIOR SOUND: Our in-ear design offers incredible sound quality with deep bass and crystal clear treble. High performance drive and poverful full-body sound rather clear voice and noise cancelling help it stay in tune works great for soundtracks audio books relaxing sounds and even techno music. Providing you high-fidelity stereo music and clear speech enjoying your wonderful sports with it.</br>ERGONOMICALLY DESIGH: With ergonomic design and premium soft smooth silicone material?? graceful curve and look fashion?? innovative sweat proof covering and flexible ear hooks that will help you stay in place no matter the physical activity. It is great for gym?? running