[Accurate Identification] This visual fault locator can easily and accurately detect and locate fiber breaks, poor connections, bends, or cracks. It operates in CW or pulse mode. The VFL emits 650 nanometer red light for fiber tracing and positioning. Breaks or faults refract the light within the fiber, making them visible. [Excellent Function] The fiber tester offers multiple functions including constant output power, low battery warning, long battery life, and long-distance detection. Efficient fiber routing and continuity checks produce a bright light at the fault location. [Wide Application] Features universal 2.5mm connectors compatible with LC, SC, and FC ports, suitable for both round and square fiber optic cables. Tests single-mode and multi-mode fibers. Ideal for use in integrated wiring systems and fiber optic engineering, CATV network maintenance, optical communication, optical measurement, and optical equipment manufacturing and research. [Detection Distance] This visual fault locator features a 30mW strong light source with constant output power. The bright red light can travel up to 20-30 kilometers in fiber optic cable. Equipped with a high-efficiency power supply circuit for stable performance in both continuous wave and pulse modes. [Practical Design] Includes battery—no additional purchase required. Compact and lightweight pen-style design with carrying case and hanging rope for easy portability. Designed with a stainless steel tip and aluminum body for durability against impact 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 variations in the color of the item in images compared to the actual product.