The Sony MDR-E9LP is a stylish set of black in-ear headphones that deliver powerful bass and quality sound for users on the go. Designed for use with most music players, the Sony in-ear headphones feature an open-air earbud style that allows in just the right amount of ambient noise while still allowing the buyer to experience quality sound reproduction. These headphones weigh approximately 22 oz and therefore are lightweight and easy to handle. The Sony MDR-E9LP is equipped with a 13.5 mm driver with neodymium magnets which allows these headphones to deliver powerful bass. It also has an impedance of 16 Ohms. These in-ear headphones have a frequency range of 18 Hz to 22000 Hz. The Sony in-ear headphones have a sensitivity of 104 db/mW with a maximum capacity of 100 mW. The Sony in-ear headphones feature an l-shaped nickel-plated 3.5 mm stereo mini plug with a y-shaped cord length of 3.9 ft.