Bluetooth earbuds, comes with a charging case, and can be a perfect solution for your wire tangling problem, along with being an ideal promotional product. Imprint your brand/logo for promotion. Features Bluetooth version: Bluetooth V5.0 Speaker size: 10mm Frequency: 20-20KHZ Battery capacity of charging case: 200mAh Effective distance: 10 meters Built-in battery capacity: 40mAh Music playing time (70% of the battery): 3 hours Charging time: about1.5h