Sony MDR-XB400 XB Series Extra Bass Headphones (Black) Specially designed, powerful drivers deliver deep and powerful bass that perfectly complements todays popular music genres. Slim in stature with swivel-fold earpads, Sony MDR-XB400 headphones are lightweight when worn, yet easily stow away in a backpack or book bag when on the go. A tightly sealed acoustic design allows for a high level of sound isolation which aides in the reproduction of powerful and extended bass sound. The durable, 1.2 m flat cord has a serrated finish that reduces tangles, so you can get caught up in your music, not your cord. Newly-developed seamless, noise isolating ear pads use pressure relieving urethane foam for not only an outstanding fit, but reduced ambient noise.