It uses upgraded Bluetooth-compatible 5.1, which gives it faster transmission speed and more stable connection.Owing to the use of CVC8.0 intelligent noise reduction, the earphone can can restore highly clear calls. You can easily adjust the comfortable wearing angle as it has independent adjustable rotating shaft design.Using high-quality ABS material, the earphone is skin-friendly and lightweight to use.The length of the product is 12cm, the width is 6cm and the height is 2cm.It is suitable for business, driving, cycling, fitness, outdoor and so on. Multi-function button group can realize precise operation. The charging box has digital display, so you can check the power level of the headset anytime and anywhere.Item Name: Bluetooth-compatible EarphoneMaterial: ABSModel: YYK-525 Style: A: with Charging Box, B: without Charging Box (Optional) Bluetooth-compatible Version: 5.1 Transmission Distance: 10m Charging Box Battery Capacity: 500mAh (Included) Earphone Battery Capacity: 100mAh (Included) Charging Voltage/Current: 5V/1A Play/Talk Time: About 10 Hours Charging Time: 1-2 Hours Compatible System: for Android/for iOS Features: Adjustable, Noise Reduction, Long StandbySize Details: Size: 12cm x 6cm x 2cm/4.72" x 2.36" x 0.79" (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:Style A: 1 x Bluetooth-compatible Earphone 1 x Charging Cable 1 x Charging Box or Style B: 1 x Bluetooth-compatible Earphone 1 x Charging Cable