[Accurate Identification] This visual fault locator can easily and accurately detect and locate fiber breaks, poor connections, bends, or cracks. It operates in both CW and pulse mode. The VFL emits a 650 nanometer red light for fiber tracking and positioning. Breaks or malfunctions will cause the light to refract within the fiber.[Excellent Function] The fiber tester offers multiple features including constant output power, low battery warning, extended battery life, and long-distance detection capability. Efficient fiber routing and continuity checks produce a bright visible light at the fault location.[Wide Application] Features a universal 2.5mm connector compatible with LC, ST, SC, and FC adapters, suitable for both round and square fiber optic cables. Tests both single-mode and multi-mode fibers. Ideal for use in integrated wiring systems and fiber optic engineering, CATV network maintenance, optical communication, optical measurement systems, and optical equipment manufacturing and research.[Detection Distance] Equipped with 30mW strong output power and constant power output, this visual fault locator can detect faults up to 20-30 kilometers in fiber optic cables. High-efficiency power circuit ensures stable performance in both continuous wave and pulse modes.[Practical Design] Includes a batteryno additional purchase required. Compact, lightweight, pen-shaped design with carrying case and hanging rope for easy portability. Features a stainless steel tip and aluminum body for durability against impacts and dust. Grounded shell design helps protect against electrostatic discharge.Color: Black Material: Metal + Plastic Size: 17.5 x 2.6 x 2.6 cm Package Contents: 1 x 30mW VFL Red Light Pen 1 x Carrying Case 1 x Hanging Rope 1 x AA Battery Note: Lighting and display differences may cause slight color variation between the image and the actual item. Measurement tolerance is +/- 1-3 cm.