Mini Bluetooth Receiver, UMsky 2016 Bullet Style Smart Wireless Bluetooth Car Kit with Built-in Mic Mini Bluetooth V4.1 Receiver Adapter for 3.5mm AUX Audio for Car Speaker Headphones You can use this wireless receiver adapter to listen music,phone calls and GPS when you are driving. Use it connect 3.5mm headphone jack to make your headset become wireless bluetooth headphone. Just one second to make your speakers become bluetooth speaker. Small and exquisite special deign to bring you new audio-visual feast. Work time: Music 5 hours/Talk 5 hours. Size:5X1.2CM.