The AFL FR1-SMF-1000-ASC-USC (Millennium Part #542538) is a singlemode OTDR fiber ring accessory used to extend the effective test range and eliminate the dead zone near an OTDR's launch point. Featuring ASC to USC connector interfaces and a 1000-meter fiber length, this launch cable ensures accurate, full-length OTDR testing of fiber optic links from the very first connector. It's an essential companion for technicians using OTDR test equipment to certify fiber optic cable, splices, and connectors during installation and troubleshooting. A must-have accessory for any fiber optic testing kit focused on precise OTDR trace results.