The new closed-back Sennheiser HD 4.50BTNC headset delivers everything required by a music aficionado with an active lifestyle. There’s the stunning Sennheiser sound and the latest wireless technology, all crafted in an elegantly minimal yet robust design, made from the highest-quality materials. But most of all, Sennheiser’s NoiseGard™ active noise cancellation lets you enjoy your music in peace – everywhere.