Features Strong Penetration: The fiber optic cable tester with imported laser head, strong red light, high heat conductor, good beam concentration effect, for easy penetration of 10km fiber, outstanding performance. It can easily penetrate long-distance optical fiber. Slider Switch: The red light pen tester use slider switch allows you to control the status of the red pen as you like. Easily and accurately detect and locate fiber breakage, poor connection, bending or cracking, select whether the switch slides up or down as required. Resistant to Falling and Anti-wear: The aluminum alloy fiber optic cable tester is resistant to falling and anti-wear, and the body is made of metal to prevent damage during use. The frosted paint baking process is adopted, which has good oxidation resistance and corrosion resistance. Durable: Sophisticated craftsmanship, durable and has long service life. Metal pen body, exquisite workmanship, powered by 2 pcs of AA battery,convenient for switching could use for a long time. Wide Application: The visual fault locator suitable for a variety of optical fiber interfaces, suitable for generic cabling system and optical fiber engineering, cable TV engineering optical network maintenance, optical communication, optical measurement drive engineering, production and research of optical devices. Specification: Item Type: Fiber Optic Cable Tester Material: Aluminum Alloy Output Distance: 10km Output Wavelength: 650nm Battery: 2 x AA Battery(Not Included) Battery Lifespan: >12h Package List: 1 x Light Pen  1 x Pen Bag 1 x Pen Strap 1 x Users Manual 1 x Spare Hose Package List 1 x Light Pen 1 x Pen Bag 1 x Pen Strap 1 x Users Manual 1 x Spare Hose