Specifications:The latest bluetooth version 4.1.Support for bluetooth stereo music playback.Allows you to conveniently answer calls while driving.Can connect two phones.Type: Bluetooth Wireless EarphoneSound Track: StereoEarpiece: SingleTransmission Range: 10mFit Design: In-Ear OnlyCompatible Brand: UniversalEarpiece Design: Earbud (In Ear)Bluetooth Version: Bluetooth V4.1 + EDRStandby Time: 100 HoursCharging Power: DC5V Power Interface [The Hole] (Computer USB Port, Mobile Phone Charger, Car Charger.)Compatible: for Android iOSSize: 3.5cm x 2.3cm/1.38" x 0.91" (Approx.) Notes:Due to the light and screen setting difference, the item's color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement. Package Includes:1 x Wireless Bluetooth Headset (with Built-in Rechargeable Li-ion Battery)1 x USB Charging Cable1 x User Manual1 x Assistant Headset (with Wire)