1、[Non Contact] Our VFL red light pen tester is non contact connection, non destructive optical fiber and transmitter end face, output power is not affected by voltage fluctuations. 2、[Function Description] The pen visual fault locator is a device specifically designed for the design and maintenance of optical cables and lines. Used to locate cables and defects on cables and visually search for fiber breaks and use defective optical cables. 3、[Output Distance] This pen type red light VFL tester has 50km output distance and the output wavelength is 650 plus or minus 10nm. 4、[Kit Contents] VFL visual fault locator red light pen kit contains 1 VFL, 1 ceramic core, 1 adapter, 1 storage bag and 1 lanyard. 5、[Energy Saving and Portable] Small size, light weight, this VFL visual fault locator is energy saving, easy to carry while stable output power is a good tool for optical fiber testing.