RETAIL $999 EVERYTHING INCLUDED ORIGINAL PACKAGING AND BOX, NEVER USED. The Koss E/9 Electrostatic Stereo Energizer ESP9 Studio Stereophones are a vintage pair of over-the-ear headphones known for their high-quality sound and stereo capabilities. These black headphones have a headband form factor and come with two earpieces for a comfortable fit. Made in the United States, they are wired for easy connectivity and are ideal for studio monitoring purposes. The Koss brand is synonymous with audio excellence, making these vintage headphones a desirable choice for audiophiles and music enthusiasts looking for a classic listening experience. QN 1149