Description: This is an OLED wireless Bluetooth 5.0 Receiver. After the mobile phones, computers, PDAs and other digital products are connected to the device, you can enjoy Bluetooth-compatible music or hands-free calls through the device. OLED work display screen, simple human-computer interaction operation, the operation is more convenient. With Aux interface, you can upgrade the car or home to a Bluetooth-compatible audio, listen to music wirelessly, and enjoy free music. Hands-free call, one-click answering of incoming calls. Built-in 250MA battery, long battery life. 3.5mm output interface design, and more versatile. Back clip design, easy to carry. Specification: Model: B31 OLED Bluetooth 5.0 Receiver Size: 60.5 x 37 x 17mm (with back clip)/2.4 x 1.5 x 0.7 inch Bluetooth Version: Bluetooth V5.0 Support Protocol:A2DP ,AVRCP ,HFP ,HSP Working Frequency 2.402GHz -2.480ghz Receiving Sensitivity -90db At 0.1% BER Working Current: 30MA (Screen Off) Built-in Battery:250MAh Charging Current:200MA Charging Time: 2 Hours Use Time:10h Bluetooth-compatible Distance:10m (Open Area) Charging Method: Micro USB 5V Output Connection : 3.5mm Stereo Interface Compatible With Androids, Mobile Phones, and Other Equipment With Aux Input Function. Package Includes: 1 Piece Bluetooth Audio Receiver Transmitter 1 Piece Micro USB Line 1 Piece 3.5mm Aux Cable 1 Piece Operating Instructions 1 Piece 3.5mm Audio Adapter Note: 1.Please allow 1~3 cm error due to manual measurement, thanks. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Please understand, thank you.