Single-End Crimp Testing: Even with one end of an RJ45 cable, the tester provides accurate crimping diagnostics, showing correct and incorrect connections instantly. High-Precision Optical Power Testing: Measures optical power and detects light attenuation levels with. 9-in-1 Cable Testing Multifunctionality: Combines 9 key functions including wire mapping, digital cable tracing, port flashing, cable length measurement, PoE checking, crimping test, OPM (optical power meter), VFL (visual fault location), and NCV (non-contact voltage) test, streamlining network. I mostly test Ethernet with it and the RJ45 tester catches bad crimps and ghost connections fast. The VFL and LED are genuinely useful extras. Built tough and rechargeable, you cannot beat it. Reliable tool for my home network setup. I terminated Cat6 runs throughout the apartment and this made. Optical Power Measurement - Can measure single-mode wavelengths like 1310, 1490, 1550, and 1625nm with measurement range from -60 to +8dBm. With a strong light source, it is easy to penetrate long-distance. 【3-in-1 Professional Tool】 Combine an Optical Power Meter, a Red Light Source (VFL), and an RJ45 Network Tester in one compact device. Perfect for fiber optic installation, maintenance, and troubleshooting, saving you the cost and hassle of carrying multiple tools.