- VFL Fiber Optic Pen---This pen type fiber optic visual fault locator is specifically designed for maintenance of fiber optic cables and lines and can effectively locate defects on cables. This visual fault locator can easily and accurately detect and locate fiber breaks, poor connections, bends or cracks. The detector emits a bright 650nm light for fiber tracing, and a break or fault in the fiber refracts the light. Product Usage---The housing of this fiber optic red light pen is made of excellent aluminum alloy material, which is drop-proof and has good durability. This fiber optic test pen has a portable design, with non slip handle that provides a convenient and comfortable grip. Compact and lightweight, convenient for use anytime, anywhere. Stable Output---The output power of the fiber optic pen is stable with an output distance of 80 km, which is a good tool for fiber optic testing. This visual fault locator has a strong light source output power of 80mW, a highly effective power circuit that provides stable power, continuous and pulse mode. Output Parameter---The output optical power is >80mW, with an output wavelength of 650nm±10nm. This fiber optic test pen can provide stable output power, which is efficient and energy-saving. Equipped with standard 2.5mm universal fiber connector, suitable for various optictal fiber types. Has a strong light source, quick control of on off, stable performance, and high efficiency. Non Contact---This portable fiber tester adopts non connection, which does not damage the end face of the fiber optic and transmitter, the output power is not affected by voltage fluctuations, improving testing efficiency.