The ASTRO A38 combines APTX low latency Bluetooth, AAC high-fidelity Bluetooth playback with state-of-the-art Active Noise Cancelling technologies to deliver the ultimate in wireless mobility. Connect easily to any Bluetooth enabled device and drown out the world with our Active Noise Cancelling speakers. If you need to talk on the phone, the built-in microphone also uses Active Noise Cancelling technology to give you the freedom of talking in places you probably wouldn"t otherwise.