: A sub-version or internal versioning identifier used by TP-Link for specific regional or ISP (Internet Service Provider) variants.
The is an entry-level, N600 class wireless router. It operates on the 2.4GHz band only (usually 300Mbps theoretical speed). It is often confused with the TL-WR840N or the Archer series, but the WR850N is a regional variant popular in Southeast Asia, Eastern Europe, and South America. 3.16.0 0.9.1 v6031.0 Build 210407 Rel.7370n -TL-WR850N-
If you are seeing this string in a log or are using custom firmware (like OpenWrt or DD-WRT): : A sub-version or internal versioning identifier used