This portable fiber optic visual light source, model 5024, provides 1 to 6 wavelengths of highly stable output including 650nm visible red light, 1310/1550nm wavelengths for single mode fiber and 850/1300nm wavelengths for multimode fiber. As well, other optional wavelengths are available. It operates at modulation frequencies including CW, 2Hz modulation output at 650nm and CW, 270Hz, 1kHz, 2kHz modulation output at other wavelengths. The fiber optic visual light source features highly stable output power, one-touch switch operation, auto-off function, low battery power indication and a backlight LCD display for night operation. FC, PC and other adapters are available. Moreover, it has a long battery life of 45h.