Sony WH-1000XM4. The item has been used only few times. Industry-leading noise reduction with Dual Noise Sensor technology Next-level music with Edge-AI, developed in collaboration with Sony Music Studios TokyoUp to 30 hours of battery life with fast charging (10 min charge for 5 hours of playback) WH1000XM4 Touch Sensor controls to turn on playback pause, skip tracks, control the volume, activate your voice assistant and answer phone calls. Talk-to-chat technology automatically reduces the volume during conversations Superior call quality with accurate voice recording. Wear detection pauses playback when the headphones are taken off Seamless multi-device pairing. a personal listening experience Updated design relieves pressure for long-lasting comfort. Frequency response 4Hz-40,000Hz