The Pyle PHPNC15 Folding Noise-Canceling Headphones reduces background noise in any environment. They're ideal for use while traveling - on planes, trains and buses alike. The closed-style headphone forms a seal around your ear as a first wave against noise - then, if you choose, turn on the active noise canceling technology to further reduce outside ambient noises by 83%. And when you're not using them, conveniently fold them up thanks to the foldable headband. Uses a 3.5 mm plug. It requires 2 x AAA batteries.