The UNI-T UT693D is a handheld optical multimeter designed for testing and maintaining fiber optic networks. It combines the functions of an optical power meter and a visual fault locator (VFL) in a single unit.   

Features:

Optical Power Meter: Accurately measures optical power within a wavelength range of 800nm to 1700nm. It supports multiple calibrated wavelengths (850, 980, 1300, 1310, 1490, 1550, 1625, and 1650 nm) and displays readings in both linear (mW) and logarithmic (dBm) units simultaneously. It also features user self-calibration, wavelength memory, and reference power memory functions.   
Visual Fault Locator (VFL): Includes a 10mW red light source (650nm wavelength) to visually identify breaks, bends, and faults in optical fibers over an approximate range of 8-10 km. It offers both continuous and pulse operating modes.   
Versatile Connectors: Equipped with universal FC/SC/ST adapters for compatibility with common fiber optic connectors.   
Rugged Design: Features an IP65 rating for dust and water resistance and can withstand a 2-meter drop, making it suitable for field use.   
User-Friendly: Includes a backlit LCD for clear readings in various lighting conditions, low battery indication, and auto power-off to conserve battery life. It also has a wavelength memory function to recall previous settings.
  
In summary, the UNI-T UT693D is a practical and robust tool for technicians and engineers involved in fiber optic cable installation, maintenance, and troubleshooting. Its integrated power meter and VFL functionalities streamline testing procedures.