There are several "TV Repair" groups on Telegram where technicians share .bin and .pkg files for specific board numbers. Common Firmware File Details File Name: Usually ends in .bin or MstarUpgrade.bin . File Size: Typically ranges from 500MB to 1.2GB.
Based on the alphanumeric string , this appears to be a specific Board ID , Hardware Model , or Serial Number typically associated with Android TV Boxes or Streaming Devices . hktrt2843p639 firmware link