8. How to distinguish between the left and right channels?

Left/L: blue

Right/R: red

The FD3/FD3 Pro has unit markers on both earphone units: blue L on the left channel and red R on the right.
Other than the letter marker, there are corresponding colors at the position of the MMCX connectors, left blue and right red. Please fit the correct channel according to the indication markers when changing the cable.