Usually the final digits refer to the country code (for the country of intent). If they vary, check that your retailer is reputable and can answer these issues.

If a unit is sold in the United States, and it was designed for use in a different country, it may not be supported or warrantied, and the code may vary based on that. Other distinctions, such as tuner type (PAL, NTSC, SECAM) may vary by region, and these codes help determine that also.

I don't have a list of codes that I can publish that will decipher these, however. My best recommendation is to purchase from an authorized Samsung reseller, or a dealer that you trust.