The headphone splitter works with any device that has a 3.5mm port, including MP3 players, CD players, smartphones and media players. With key chain cap, you can take the headphone splitter anywhere and its double auxiliary jacks allow you to connect two sets of headphones so you and a friend can listen to music together on the bus or watch a movie from the same laptop on a plane ride.It's a great solution to share cool music, movies and games with your families and friends.