BELKIN PURE AV AM20002-03 3 feet Digital Optical Audio Cable M-M (Discontinued by Manufacturer) Belkin Digital Optical Audio Cable 3 Feet. AM20002-03 Digital Optical Audio Cables use superior-grade optical fiber to deliver better clarity and a more natural sound from your digital audio video components. Transfers digital signal accurately using superior-grade, optical fiber Installs easily with ergonomic, non-slip grip construction