Features: brand new and high quality Comfortable to wear,easy to use,suitable for left or right ear. for Creative hook design and lightweight,stable and comfortable. Support adjust volume and change music，Strong compatibility. The headset has voice prompts(power on, power off, pairing, connected, disconnected,low battry) and so on. Phone numbers can be broadcast when calls come. Long press the function for key for about two seconds to realize power on, then the blue light lights up. After power-on prompt tone, the red light and blue light flash alternately, enters bluetooth-compatible pairing state. After the phone and headset are successfully connected, the bluetooth-compatible headset will automatically connect when it is on for the next for time. After the second mobile phonand bluetooth-compatible are paired sessfully, turn on the first mobile phone's bluetooth-compatible again, click on the previously connected ，bluetooth-compatible and the headset will connect to both mobile phones simultaneously. Specifications: Bluetooth-Compatible Version: V5.1 + EDR Bluetooth-compatible transmission distance:About 10 meters/33 feet.<br/> Power:0.25MW-2.5MW Working Voltage / Current:3.7V/ 8mA Charging Voltage / Current:5V +0.25V/1A Charging: About 1-2hours Standby:About 688 hours Calling Time:About 48 hours Frequency: 2. 402GHZ~ 2.480GHZ Agreement: A2DP AVRCP HFP HSP Transmission Intelligent Reminder: voice prompts/ call number broadcast Wearing: the style to hang behind ears and be plugged into ears Battery Capacity: 300mAh Li-battery Charging Power: AC Input 110-240V, for DC Output 5V/1A Package Includes: 1x Rear-mounted in-ear Bluetooth-Compatible Headset 1x Plug-in Headset 2x Earbuds 1x USB Charging Cable 1x User Manual note: Due to the differences between different monitors, the picture may not reflect the actual color of the item. Due to manual measurement, please allow an error of 1-2 for cm.