This optical laser light source is a stabilized high power light source, which is used in the field of fiber optic network installation and maintenance. The application range of the OPTISource dual wavelength MM 850nm / 1300nm fiber optic light source is, due to its high quality processing and reliability, in the field of fiber optic attenuation measurement, fiber optic signal loss measurement and fiber optic cable identification via light source modulation. There are three models: 850/1300 nm for multimode networks (part no. 257821), 1310/1550 nm for singlemode networks (part no. 257822) and the dual device for multimode and singlemode networks (part no. 257823) for all four wavelengths. The application range of the Hobbes OPTISource, due to its high quality workmanship and reliability, is in the field of fiber optic attenuation measurement, fiber optic signal loss measurement and fiber optic cable identification via light source modulation.