Feature:1. 20KM TESTING: This fiber visual fault locator has a longer penetration distance of 20KM, with stable performance, and long service life.2. 2.5MM CONNECTOR: This visual fault locator uses a universal 2.5MM connector and supports common interfaces for FC, SC, and ST.3. DETACHABLE DESIGN: The metal pen head of the fiber optic source tester is detachable, making it easy to replace the ceramic core.4. WORK PRINCIPLE: The VFL pen is driven by constant current source and connected to the optical interface to enter multimode and single mode optical fibers, achieving fault detection function.5. MULTI PURPOSE: This red light pen is an indispensable tool for fiber optic engineering construction, fiber optic network maintenance, and optical device production and research.Specification:Item Type: Fiber Optic Visual Fault LocatorMaterial: ABSOutput Distance: 20KMWavelength: 650NM10NMFiber Optic Connector: Universal 2.5MM ConnectorWorking Temperature: +10 to +45Flashing Frequency: 1HZWorking Humidity: 30% to 90%Battery Type: AAA Battery x 2 (Not Included).Package List:1 x Fiber Optic Visual Fault Locator1 x Storage Bag