Feature: 1. ACCURATE MEASURING: Adopt a highly sensitive chip, this optical power meter can measure accurately and quickly, without any preheating time. 2. 30KM RED LIGHT SOURCE: With a visual fault locator function, the red light source detection distance is up to 30km for meeting various needs. 3. RJ45 NETWORK TESTING: Also has a RJ45 network testing function, this fiber tester allows you to quickly check and correct network cable wiring. 4. MULTI FEATURES: Featuring multiple functions, including relative power calculation, calibration function, automatic shutdown function, this fiber tester is highly practical. 5. WIDE WAVELENGTH RANGE: The optical power meter supports a wavelength range of 850 to 1650nm, can cover most requirements of communication engineering maintenance. Specification: Item Type: Optical Fiber Power Meter Material: ABS Red Light Source Detection Distance: 30km Power Supply: 3.7V lithium battery x 1, capacity 650mAh (built in) Probe Range: InGaAs Wavelength Range: 850-1650nm Standard Wavelengths (nm): 850, 980, 1270, 1300, 1310, 1490, 1550, 1577, 1625, 1650 Display Resolution: Linear display: 0.1%, logarithmic display: 0.01dBm Working Temperature: -10℃ to +60℃ Storage Temperature: -25℃ to +70℃ Automatic Shutdown Time: 10 minutes Battery Continuous Working Time: Not less than 40 hours. Package List: 1 x Optical Fiber Power Meter1 x User Manual1 x USB Cable1 x Lanyard