Sony made the MDR-AS20J sport-style headphones for active use. The loop-shaped ear hangers comfortably fit over a wide range of ear sizes, and keep the earbuds in place even during intense workouts. A four-foot cord gives you plenty of room to move around, while the included clip secures the cord to your clothing. The low-impedance design features 13mm drivers for high-energy sound with virtually any portable audio player.