Foldable headphones: When not in use, the headphones can be folded for easy storage and carrying Soft earplug ensures full comfort even if used for long hours Built-in microphone: play/pause/next/previous button for convenient audio controls Support Bluetooth mode + FM radio mode + Micro SD Card playback mode + Aux Mode Built-in rechargeable lithium-polymer battery. Charging interface: Micro USB Working Voltage: DC 5V The microphone only works in the Bluetooth mode What's in the box 1 x ST11 Wireless Bluetooth Headphones - Rose Gold 1 x USB Charging Cable 1 x 3.5mm to 3.5mm Audio Cable