Versatile 4-in-1 Functionality: The ET636 ET638 Network Cable Tester combines four essential tools into one device, featuring a Multi-function Fiber Optical Power Meter, Visual Fault Locator, Multimeter, and comprehensive Network Cable Tester capabilities for efficient troubleshooting. Accurate Cable Length Measurement: This Network Cable Tester can measure Ethernet, telephone, and coaxial video cable lengths up to 600 meters. Advanced Network Cable Analysis: With the ET636 ET638, easily identify open circuits, short circuits, crossover connections, and perform crystal head crimping tests. High-Performance Optical Power Meter: The optical power meter design ranges from 6dBm to -70dBm and is compatible with ST, SC, and FC interfaces. User-Friendly and Eco-Friendly Design: Featuring a 3.2-inch color display and supporting multiple languages including Chinese, English, German, and Spanish, the ET636 ET638 Network Cable Tester is powered by rechargeable lithium batteries, offering both convenience and environmental sustainability., Manufacturer: MINING