Features:Transmitter Testing Function: including cable continuity testing, cable scan, port flashing, cable length measurement, PoE test, QC testing for crystal head, OPM(optical power meter) and VFL(visual fault location) function.POE Test: automatic identification of midspan/endspan/power by 8 cores, automatic identification of standard and nonstandard device.Optical Power Meter: 850/1300/1310/1490/1550/1625nm wavelength switching; unit switching at dBm, dB, or mw, uw, nw; and REF switch.Visual Fault Location Function: detect and locate fiber breaks, as well as problems such as poor connections, fiber bends or cracks.Receiver Function: sensitivity adjustment, 300m no-load shielded network cable/non-empty shielded network cable, NCV detection, lighting function, etc.Non-contact Voltage Detecting: the receiver can be used to detect the AC voltage of household electrical wiring.Illuminate Function: the receiver designed with lamp for auxiliary lighting up the working areas during operation.Battery Operated: both the transmitter and the receiver are built-in with 1500mAh polymer battery, no need to change batteries, type-C charging, with charging indicator and low battery indicator.Other Settings: backlight brightness(level 1/2/3), backlight time(MAX/1min/30S/15S), auto-off time(15min/30min/1h/2h/off), red light flash under VFL function(fast flashing/slow flashing/ON).Wide Applications: suitable for the network line engineering and maintenance work of telecommunication, computer, other metal conductor, etc.Specifications:Material: ABSCable Type: CAT5/CAT6Voltage: 60VPackage Weight: 586g / 20.67ozPackage Size: 24 * 16.5 * 5.5cm / 9.45 * 6.50 * 2.17inTRANSMITTER:Wiremap Port: RJ45Remote Continuity: 300mCable Sequence and Fault Test: YesSTP/NTP: YesShort Circuit Reminder: YesAnti-jamming and Normal Mode: YesAudio Transmission Frequency: 455KHzAudio Transmission Distance: RJ45 300mNVL: 10mWPower Meter: 850/1300/1310/1490/1550/1625nm (wavelength)Crimping: RJ45-8 cores, min length is 10cmLow Voltage Prompt: <3.5V±0.1V, power indicator flashesPower Supply: 3.7V 1500mAh polymer lithium batterySize: 148 * 70 * 32mm / 5.83 * 2.76 * 1.26inRECEIVER:Scan Current: 300mARemote Continuity: 300mNCV Detection: YesLamp: YesLow Voltage Prompt: YesPower Supply: 3.7V 1500mAh polymer lithium batterySize: 198 * 50 * 28mm / 7.80 * 1.97 * 1.10inPackage List:1 * Transmitter1 * Receiver1 * RJ45 Adapter Line1 * RJ11 Adapter Line1 * Crocodile Clip Test Line1 * Type-C Data Cable1 * Carry Bag1 * Manual (English)Please note that due to unfavorable user feedback, the headphone accessories have been discontinued. Thank you.