OLS2 is a dual-wavelength light source with a single output port. It comes in two models; one with 1310 and 1550nm wavelengths, and another with 1550 and 1625nm wavelengths. It features four operating modes: dual-wavelength ID, single-wavelength ID, continuous wave (CW), and identification tone. The ID output is designed to work with Loius' optical power meters for automatic dual-wavelength identification, improving testing efficiency. The output ports are equipped with user-replaceable adapters, which not only allow for easy replacement but also facilitate cleaning.