This item is a dual use transmitter and receiver. It is suitable for your car, home, or portable audio device with capability to wirelessly stream music from your smartphone, tablet or computer. Instantly upgrade your favorite speaker by connecting it through its AUX line-in port, or even add to your favorite pair of headphones with the included 3.5mm audio cable. Feature - It is able to change the traditional speakers into -enabled ones. - Built-in 600mAh Battery ensures up to 8 hours working time, you can enjoy wireless free all day long. - Advanced noise deduction and echo cancellation technology offers you wonderful sound quality. - There is no need to download any app to pair your device. - Compatible with almost all audio device on the market. Specification - Color: Black - Size: 97 x 58 x 8.2mm (L x W x H) - Working Frequency: 2400MHz - Transmission Rate: 2.1M or s - Version: 5.0 - Support Protoclo: A2DP, AVRCP, HFP, SPP HID - Working Range: about 10M or 33feet - Working Time: about 8h - Battery Capacity: 600mAh Note: 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.