Sennheiser PXC 550 Wireless &ndash; NoiseGard Adaptive Noise Cancelling, Bluetooth Headphone with Touch Sensitive Control and 30-Hour Battery Life Bluetooth 4.2 wireless technology in an ergonomically designed lightweight, comfortable and collapsible travel headset perfect for travel. Connectivity Technology: Wireless NoiseGard adaptive noise cancellation ensures superior sound quality in every environment. Impedance:Active 490 Ohm/ Passive 46 Ohm Intuitive user control and convenience thanks for voice prompts, touch controls, NFC pairing, smart pause and automatic on/off Triple microphone array delivers business class communications with exceptional vocal clarity..Sennheiser sound signature quality with selective sound modes to enhance the listening experience The PXC 550 wireless is fully compatible with CapTune, sennheiser's premium quality music player and powerful sound tuning app to perfectly adjust the feel of your music to your personal preference