AFL OFI-400 Optical Fiber Indentifier are designed to detect and measure the core power levels of optical signals on singlemode optical fiber without disconnecting or cutting the fiber. These instruments are simply clamped onto a fiber and indicate the presence and direction of traffic, continuous test signals and modulated test tones. This permits network personnel to easily and quickly identify a specific fiber without risk of revenue service disruption. The NOYES OLS7, OLS2, CSS1-SM and CSS1-MM series of optical light sources are ideal companions for the OFI-400 optical fiber identifiers.