Music Bullet's?sound destroys the competition! The Music Bullet?converts the flat sound of MP3 players, cell phones or computers into rich sound, deep bass and penetrating rhythms sure to wow your audio senses. Connects via speaker jack. Makes phone conversations clearer than ever. Take with you anywhere: beach, work, car, camping. Use more than one for wall-to-wall sound. Comes assorted colors, black or red, let us choose. Rechargeable battery, included. Plastic, 2 1/4"L x 2"W x 2"H.