Features: The sensor are sensitive, stable and reliable. You can use flashlight in dark environment. High-quality protective cover, safer protect. Wear headphone-jack, so that maintenance technicians can work conveniently and comfortably in noisy environment. For telecommunication network line engineering and daily maintenance, computer network line engineering, other metal line engineering and maintenance work. Package Includes: 1Set Cable Detector Specifications: Material: ABS, LED Signal Tracing Transmit Distance: More Than 1KM Display: LED Operating Temperature: -10 to 40 / 14 to 104 Storage Temperature: -20 to 60 / -4to 140 Size: As Shown note: 3xAAA batteries needed for transmitter(NOT Included), 1x6F22 9V battery needed for receiver(NOT Included). To prevent electric shock and personal injury, DO NOT: Use strong electricity to track the cable to avoid personal injury / or equipment damage. Use this machine in thunderstorm-weather to avoid causing personal injury / or equipment damage. To avoid damage to the equipment and objects, note the following: For power cables, do NOT use the cable sequences verification function. If the product not expected to be used for long period, please remove the battery to avoid battery leakage, corrosion and poor battery-contact.