B:The wavelength of the fiber on the ground side is 1550nm The interface is defined as: RX/TX/AV/VCC/GND RX is connected to the CRSFTX of the flight control, and TX is connected to the CRSFRX of the flight control The AV on the ground side is output to the AV signal input port of the display or VTX, and the VCC power supply voltage is 5.5V-26V Dimensions: length x width x height - 50mmx30mmx8.5mm Power supply: 5.5V-26V: (2S-6S battery) (Not included batteries) Power consumption: less than or equal to 5W Communication interface: MX-SH1.0mm-5P: CRSF interface/CVBS video port Fiber optic interface: FC: Communication distance: maximum 40KM Note: The product indicator lights from top to bottom are: power light, fiber optic light, video light, data light; GND is the ground wire, VCC is the power supply, AV is the video, TX is the TTL signal output, and RX is the TTL signal input. Due to different batches, there may be differences in product appearance, color, and printed text, which not affect the use. Color: As shown Material: PC+Plastic Package Contents: 1 * Module 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.