PHILIPS USA HS-740 In-ear Headphones with Ccaw Voice Coil 10Hz - 20,000Hz frequency response Copper Cladded Aluminum Wire (CCAW) improves sound quality Adjustable ear-loop for maximum comfort and stability 15mm Neodymium speaker element for exceptional sound quality Asymetric 4 ft. OFC cabling system with gold-plated 3.5mm plug