The Optical Time Domain Reflectometer (OTDR) Launch Cable Box shown in the picture is 1000 meters (1 km) long, single-mode fiber, with SC/UPC to LC/APC connectors. Functions and Specifications: Blind Zone Elimination: Used to connect between the OTDR device and the cable to be tested, helping the device accurately measure the start of the connection and overcome the dead zone near the measuring device. Fiber Type: Single Mode (SM). Connectors: One end with SC/UPC (blue) and the other end with LC/APC (green). Length: 1000 meters (1000M). New Price: 150 (negotiable) WhatsApp contact only