features of BT 4.2 technology, 3.5mm Audio Port, built-in Microphone and Speaker, TF Card MP3 Player, Hands-free call, Colorful LED Lights, and FM Radio, the BT Headphone is a super companion for you during daily life and travel. Features: Multifunctional: Equipped with features of BT connection, TF card music playing, AUX-IN wired music playing, FM radio, and hands-free call with Microphone. Colorful LED Lamp Effect: Spectral cycle - multicolor spectrum cycle light, color changes. Static mode - choose your favorite color from a variety of colors. AUX-IN Function: Connect to the audio devices (such as MP3/MP4, Laptop, etc) without BT function via the 3.5mm audio cable (NOT included). Ergonomic Design: Adopts telescopic headband + suspension earmuff, comfortable to wear. Foldable soft leather ear cushion, easy for storage. High-sensitive Mic: HD microphone reduces ambient noises and grasps the detail of voice. You can get high-quality hands-free phone conversation. Long Battery Life: Built-in 250mAh rechargeable battery lasts 6-8 hours of music playing time per charge cycle. Great Sound Effect: 40mm large size sound unit, excellent titanium-plated diaphragm bass shock, mezzanine fullness, clear treble. APP Control: You can download the NIA App for music playback and sound adjustment.