Visual Fault Locator: Easily identify breakpoints and bad connections on fiber optic cables. Both continuous and flashing modes are available. LED Flashlight: Support additional lighting in dark working conditions. Other features: 30mW output power Powered by 3.7V/450mAh Li-ion - Ion battery, working time > 50 hours (OPM only) Micro USB rechargeable design. Supports 500 data storage.