Key Features . Binaural Low-Latency Bluetooth TransmissionDual-Microphone Noise Cancellation for CallWearing Detection Automatic Play and; Pause3.5 Hours Playback Time Up to 15 Hours with the CaseIP54 dust and water resistant . Fast Stable and Smooth ConnectionInstead of having a primary and secondary headphone audio can be transmitted to both ears at the same time which ensures a fast and smooth transmission. Meanwhile system wide optimisations designed to eliminate delay lag incompatibility and other disturbances help to maintain your signal quality for and undisrupted listening experience Dual-Microphone Noise Cancellation during CallsNoisy surroundings cannot compete with your voice during calls thanks to dual-microphone beamforming an environmental noise cancellation algorithm and an anti-wind noise chamber Wear Detection Automatic Play and; PauseInfrared optical sensors detect whether you\'re wearing the headphones or not and therefor will pause or play your audio in response so you don\'t need to take out your phone each time. Carefree ListeningThe W31 headphones are designed to resist water and dust at an IP54 rating. Whether you\'re staying in or working out you will have confidence that your earphones are protected Enjoy Your Personal Soundtrack All DayEnjoy up to 3.5 hours of continuous music before re-docking the charging case holds up to 15 hours-worth of enjoyable music playback..