Description: 【Functions】: Multifunctional 2 in 1Network Telephone Line Diagnostic Line Tester, Use for testing your homemade Ethernet patch cables to make sure they are in working order prior to connecting to your devices 【POE Switch Testing】: Network Cable Tester, Support POE Switch online test network cable, It can directly test the crossover, short circuit, open circuit, open circuit and other on off conditions of the cable when the switch, router, PC and other equipment are charging. 【Special Features】: rj45 ethernet cable tester, Tests RJ45 cables, RJ11 telephone cables and network cables, Support Network Cable types: 4/8 core network cable, 2/4 core telephone cable. 【Two Modes to Choose】: Network lan cable tester, Standard mode and fast speed display modes, flexible and versatile 【Automatic Sleep Function】: Lan network tester, With automatic sleep function, the time is 10 minutes, to prevent from running out caused by not shut down, hand held for portability. Specification: Material: Plastic Size: 75mmx75mmx25mm/2.95x2.95x0.98inch Supported network cable types: 4/8 core network cable, 2/4 core telephone cable Maximum cable length:>1000 meters Maximum withstand voltage: 60V Power: Max 20 milliwatts Temperature: -10 -50 Humidity: 10% -80% (non condensing) Storage temperature: -10 -55 Package Includes: 1Pcs Network Cable Tester Note: Please allow slightly errors due to manual measurement and different monitors.