The following is a Linksys WHW01 router which has been flashed with OpenWRT version 25.12.5 (if you don't know what OpenWRT is, I would recommend doing some research on it before buying this).
The listing includes the router and power adapter as shown.
Note: The default configuration of OpenWRT for this model has both ethernet ports configured as LAN ports. In order to make this router usable as a standalone router or as an access point with an ethernet backhaul, I have configured the lower ethernet port as a WAN port. This can be changed back in the web interface as needed.
Specs:CPU: Qualcomm Atheros IPQ4018 (quad core, 716MHz)RAM: 256MBStorage: 256MBWireless MIMO:5GHz 2x2, 2.4GHz 2x2LAN Ports: 1x 1Gbps portsUSB ports: none