The Fiber Instrument Sales OV4 Loss Test Set contains both a power meter and light source similar to other units. This unit also measures ORL to -55dB which meets demanding field testing specifications. The OV4 has a color touch screen display which makes testing and saving test results a snap. The power meter is calibrated at 850/1300/1310/1490/1550/1625nm with a testing range of +5 to -77dB. Standard with dual MM, dual SM and quad wavelengths. Other source configurations are available.