Bluetooth Receiver 4.1 Wireless Audio Receiver 3.5 mm Headphone Adapter With Hands-Free Calling And Aux Port For Earphones Home Car Stereo Speakers; Turn on, Connect Bluetooth devices, receive mobile or other Bluetooth devices audio signal with one press.; Portable Design: Mini size with clip; Can Connect Two Bluetooth Devices At The Same Time; Built-in rechargeable lithium battery, provides up to 4 hours working time, plug and play, and only takes 50 minutes to fully charge it; Amazing Acoustics, Crisp Clear Sound