1One port outputs 2 wavelengths, entitled with high stability, it is with builtin optical isolator. 2Working continuously for 46 hours, it can be used for telecommunications repair and cable TV repair. 3Passing the fiber optic laboratory test, it can also be applicated to other fiber optic measurements. 4Made of high quality material, being practical and durable, it is entitled with extremely meaningful function. 5With dual wavelength, being stable, it can be handled for portable use. Meanwhile, it is with universal optical connector. Item Type: Dual wavelength handheld stable light source Wavelength: 1310+1550nm Output Power: -5dB Optical Connector: ForFC+SC+2.5mm universal (1.25mm LC optional) Power: Alkaline battery (2 x AAA 1.5V battery, not included) Output Stability: 0.05dB / 15mins; 0.1dB/8 hours Modulation Frequency: CW, 270Hz, 1KHz, 2KHz border: 1px solid000important;}1 x Dual Wavelength Handheld Stable Light Source1 x Adapter Interface1 x Instruction ManualBatteries are not included.Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.