Topic: 3DS Hardware versions

Hi. I have 3DS for 2 yeas. Now, my friend got one (older one).
There is a difference in 3D display (my is brighter-whitter).

I found today, that I have version CTR-S-EUR-C1 and his version is C2.
Can't find any info on Internet, what is the difference (and there is, minimal in 3d screen).

Which version you have? /it's the last text on the back side)

i only know that after a few months nintendo made a version of the normal 3ds where the touchscreen doesnt make any scratches on the topscreen anymore.