Features Fiber optic tester --- The FTTH fiber optic tester was specially developed for the maintenance of optical cables and lines and can locate defects in cables and visually search for fiber breaks. Easy to use --- Visual fault locator Conforms to ergonomic design for easier on/off. The VFL can also be used as lighting for work and operation in the dark. Better Application --- The VFL red light pen is an indispensable tool for fiber optic engineering construction, fiber optic network maintenance, fiber optic device manufacturing and research. Wide Compatibility --- Telecom Multifunction Tester Equipped with a 2.5mm universal interface for FC SC ST, the visual fault finder can be quickly charged by power bank, computer, adapter and more. Convenient Carrying --- Thanks to its light weight and compact size, the fiber optic light tester is very convenient to take with you when working outdoors. Specification: Item Type: Visual Fault Locator Test Distance: 15KM Working Current: ≤ 150mA Battery Life: >3.5h Output Level: 3 adjustable level output. Output Wavelength: 650nm Interface: 2.5mm Universal Interface Power: 2 x AAA battery, shipped without battery. Storage Temperature: -40~+85 ℃ Working Temperature: -20~+60 ℃, no condensing.  Package List:1 x Visual Fault Locator 1 x Ceramic Sleeve1 x User Manual Package List 1 x Visual Fault Locator 1 x Ceramic Sleeve 1 x User Manual