Designed to provide either 1310 nm or 1550 nm wavelengths, this optical light source is the perfect tool for providing a stable light source for single mode fiber measurements. Includes FC, SC, and LC adapters to directly connect to UPC/PC FC, SC, and LC fiber connectors. Has four different modulation outputs (CW, 270 Hz, 1 kHz, 2 kHz) at 1310 N-m and 1550 nm wavelengths.