How to read "Manufacturer Name"?

[dula714]

On my Lumia 920, Under extras + info, more info, manufacturer name, it says

RM- 820_nam_Canada_200 and a friend of mine has a Lumia 1520 and it says,
RM-937_im_mea3_1018

What does those letters and numbers mean?

 

[xandros9]

Someone more knowledgeable could shine more light on it, but I believe those to be there to distinguish slight variants apart.
There are different ROMs/firmwares for different regions and carriers, so those are slightly different variants under, say, the umbrella 1520 name.