BrainSlayer does not maintain builds for MR3420 v5. Flashing DD-WRT for TL-WR841N v13 may work but is untested and risky.
| Build | Size | LuCI Web UI | Use case | |-------|------|-------------|----------| | Factory (from stock) | ~3.8 MB | No | First-time flash | | Sysupgrade (minimal) | ~3.9 MB | No | CLI-only | | Sysupgrade (with LuCI) | 4.2 MB | Yes | Too large – will brick | tp-link mr3420 v5 firmware
✅ Correct approach: Flash factory → install luci and luci-theme-bootstrap to external USB storage (extroot). BrainSlayer does not maintain builds for MR3420 v5
⚠️ Warning: Stock firmware disables USB tethering for some newer Android/iOS phones. If that happens, consider OpenWrt. ⚠️ Warning : Stock firmware disables USB tethering
Flash OpenWrt factory image:
First boot:
Most users are satisfied with the stock firmware. TP-Link periodically releases updates for the MR3420 v5 to patch security vulnerabilities (like DNS hijacking flaws) and improve 4G modem compatibility.