Aukey EP-B4 Bluetooth 4.1 Wireless Stereo Sport Headphones with AptX, Built-in Mic for iPhone, Samsung, Android Smartphones (Black) Balanced, clean sound in a lightweight, comfortable fit for active or stationary wireless Audio consumption Better fit = better sound quality and noise isolation, find your perfect fit with 3 pairs of included ear-tips (S/M/L) Connect quickly and effortlessly manage Audio playback and calls with built-in volume controls, multifunction button and microphone Compatible with Bluetooth-equipped computers & mobile devices, up to 4.5 hours playback or up to 175 hours standby Package Contents: AUKEY EP-B4 Bluetooth 4.1 headphones, micro-USB cable, ear-tips (S, M, L)