Indicate the signal directions and in fiber Indicate the signal presence or absence(Live or dark fiber) Efficiently identifies the traffic direction and frequency tone (270Hz, 1KHz, 2KHz) with audible warning Displays the relative core Don't need to replace adaptor;Lower indication;Build in VFL function Specification Model Number: -40 Weight: 018kg Wavelength identification range: 800~1700nm Optical fiber type:30/20/09/025mm Identify signal frequency:270KHZ/1KHZ/2KHZ Accuracy:+10db~-30dBm(Continuous) +10db~-25dBm(Wave modulated signal) Sensitivity range:+10db~-50dBm Output wavelength:650 +/- 10nm colour: black + blue Material: plastic size: 28x21x240mm Package Contents: 1*Fiber Optic Identifier 1*bag Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.