If it says v5 (or Ver:5.0), proceed below. If it says anything else, stop and search for your specific version.

While some routers may display "V5" within their web-based management page, this is often a software-reported version that does not match the actual hardware version. You should always use the hardware version printed on the label on the bottom of the device for firmware updates. www.tp-link.com Key Firmware Information Version Discrepancy

Firmware updates for legacy devices like the WR340G typically aim to:

While TP-Link provides a dedicated support page for the TL-WR340G V5