The SPARKPLUG with New Improved CushionsThe SparkPlug features a dynamic element that is positioned just outside the ear and connected to a tubular port structure that is inserted on a soft expandable cushion into the ear canal. The soft foam cushion expands for a custom fit to improve isolation and enhance deep bass and treble clarity. Now with improved slow memory ear cushion made of hydrophillic, formed urethane, you are guaranteed a custom fit every time.Ths SparkPlug also featues a white cord to compliment many mp3 players. The fit enhances isolation when you want to plug out ambient sounds that interfere with the listening experience. The SparkPlug has a frequency response performance of 10Hz-20,000Hz and full Sound of Koss. Combined with your favorite music and a portable sound system, it is the ultimate accessory on the go.Built to last, The SparkPlug is covered under Koss’ No-Questions-Asked Lifetime Warranty – the only warranty of its kind in the stereophone industry.