Sony MDR-NC5 Noise Canceling Headphones with Airline Adaptor (Discontinued by Manufacturer) Reduces Noise by 70% (10dB) when noise canceling circuit is switched on Open-Air Headphone Design for lightweight comfort, hour after hour 30mm Diameter Driver delivers deep bass down to 30 Hz; provides outstanding dynamic range Folding Headband and pivoting ear pads make for easy storage in a backpack, briefcase or purse Ideal for travel and outdoor use