2-IN-1 OPTICAL NETWORK INSTRUMENTS- Support 850/1300/1310/1490/1550/1625nm wavelength Measurement range-70 -+ 10dBm. 3. Check fiber breakage, winding, etc. 4. Cable tracing & cable continuity testing function.5. Detect the crimping condition of the crystal head.6. Detect Ethernet network for Power over Ethernet existence.