Function: 1 You can choose from 6 light wavelengths of 850nm / 1300nm / 1310nm / 1490nm / 1550nm / 1625nm. 2. Universal Optical Interface Design Support FC/ SC / ST and can be converted between absolute power dBm and relative power dB. 3 Ergonomically designed and compact construction is specifically designed for fiber optic installation, operation, and maintenance without restricting space usage. 4 Easy operation, just follow the operation directions to detect accurate values easily. 5 Wide application for fiber CATV engineering, fiber optic sensing research, fiber optic device manufacturing, fiber optic device research and other fiber optic projects.