The Ether Card is an add-on for the Carrier Board, which in turn is made to fit perfectly in a standard project box. It has three 6-pin headers on the side (only 8 pins on two of the headers are actually used).
This card is based on the well known ENC28J60 chip, and is designed 100% for through-hole components, making it very easy to solder and assemble. The resulting configuration will work on any 10/100 Mbit Ethernet LAN. A small TO-92 voltage regulator is used to supply the 3.3V needed by the ethernet chip. There is a space for a larger TO-220 type regulator if extra 3.3V loads are planned.
The Kit version includes the PCB, and all the components needed to complete the board, including three 6-pin headers and an RJ-45 MagJack with status LEDs + built-in pulse transformers for correct CAT5 cable termination.
The PCB only version contains just the board. No parts, no headers.
The documentation and full design details are freely available.
Note that the Ether Card is also compatible with 5V boards, such as the Arduino and RBBB. It only needs 4..6 I/O lines + power.