Resources:
Primary Guide: Adafruit Ethernet Feather Wing
Adafruit Ethernet FeatherWing: Reliable Wired Networking for Feather Boards
The Adafruit Ethernet FeatherWing adds the stability and reliability of wired networking to your Feather projects. While wireless connectivity is flexible, certain permanent installations or IoT applications benefit from the robustness of Ethernet. This FeatherWing makes it simplejust plug in a standard Ethernet cable and enjoy instant wired Internet connectivity. Powered by the WIZ5500 Ethernet chip, it communicates over SPI plus a chip select (CS) pin, and works with the Arduino Ethernet2 library for cross-platform networking. It supports Ethernet client mode, enabling your Feather to connect to wired networks with ease. With DHCP auto-setup, link and activity LEDs, and compatibility across the entire Feather ecosystem, this board is ideal for projects that require dependable, low-latency connections.
Key Features:

Wired Networking for Feather Boards: Add reliable Ethernet connectivity to any Adafruit Feather.
WIZ5500 Ethernet Chip: Provides robust wired networking over SPI with a simple CS pin.
Arduino Ethernet2 Library Support: Easy integration with existing Arduino sketches and libraries.
Plug-and-Play Setup: Just connect an Ethernet cable; DHCP automatically assigns network details.
RJ-45 Jack with Indicators: Built-in link and activity LEDs for quick visual connection status.
Cross-Feather Compatibility: Works with all Adafruit Feather boards.
Ethernet Client Mode: Suitable for applications where the Feather acts as a client device (server not supported).
Reliable Alternative to Wi-Fi: No SSIDs, passwords, or antennas requiredperfect for stable long-term installations.