The new Sennheiser HD 4.40 Wireless offers high-quality wireless sound for every day listening on the move. The closed-back, around-ear headset features Bluetooth 4.0 and aptX compatibility to deliver true Hi-Fi sound with a satisfyingly dynamic bass. Its elegantly minimalistic design has been crafted from robust, high-quality materials to meet the requirements of the street. When you love the sound of the HD 4.40 Wireless, that’s no coincidence at all. The closed-backed design of this headset is fitted with proprietary Sennheiser drivers that came a long way before being allowed to transmit sound to your ears. So enjoy their well-balanced, amazingly detailed sound with dynamic bass. The HD 4.40 Wireless is about freedom of movement. Instead of a cable, you get the latest wireless technology and audio codec with Bluetooth 4.0 and aptX for reliable transmission and true wireless Hi-Fi sound. Meanwhile, Near Field Communication (NFC) ensures immediate and simple pairing with compatible devices.