Accurately test whether a single network cable transmits signals normally. Added wavelength memory function to remember the test wavelength set before shutdown after shutdown. Press LIGHT in different environments to turn on or off the backlight at will. Added LED flashlight lighting function to facilitate line inspection in dark environments. You can perform automatic adjustment of test reference according to actual test requirements. Encapsulated protective case can reduce the damage to the machine caused by accidental drops to a certain extent. Specifications: Test range: -70 to +6dbm Wavelength range: 800~1700nm Standard wavelength: 850nm, 980nm, 1300nm, 1310nm, 1490nm, 1550nm, 1625nm, 1650nm Uncertainty: ḟ 5% 650m red light source (optional): Imw, 10mw, 20mw, 30mw Display resolution: linear display 0.1%, logarithmic display 0.01dBm Battery: 2 * AAA batteries, 1.5V, 250mAh Item size: 130 * 63 * 29mm / 5.1 * 2.5 * 1.1in Item weight: 310g / 10.9ounce Package size: 260 * 150 * 100mm / 10.2 * 5.9 * 3.9in Package weight: 350g / 12.3ounce