Take in the world around you as and when you want with the Bang & Olufsen E4 Noise Cancelling Earphones. Complete with the latest ANC technology, this set gives you silence when you need it most so you can really focus. In addition, the E4 Earphones also have transparency mode. With this, you can control the level of ANC to suit your environment. This is perfect for those in the city where honking horns and sirens are vital interruptions. Superbly comfortable and classically sleek, the E4 Earphones use stainless steel and rubber for a high-quality design. In addition, this audio system is designed for all-day wear. They sit easily in your ears so the 20-hour battery life is nothing short of wonderful.