Three signal frequencies can be identified: 270Hz/ 1kHz/ 2kHz. Fiber optic direction accurate identification: when there is signal in the oprical fiber, the left and right lights show the signal direction. When the left light is on, the light source is from right to left. Optical fiber identifier visual fault locator, online testing doesn't require fixture replacement, single mode, multi-mode, . Press down the back trigger to clamp the fiber and start testing automatically. Stable and strong beam concentration, effectively cooperate with line direction. Hign-concerned Chemical:None Connector Type:Hybrid Model Number:-C605 (The product appearance and printed words depending on the batch, but this does not affect use) Colour:Black Material:plastic Package Contents: 1 x identification device 1 x data cable 1 x bag 1 x lanyard 1 x Chinese and English instruction manual Only the above package content, other products are not included. Note: Light reflection 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.