Gowoops W5100 Ethernet Shield Network Module with Micro SD Card Slot for Arduino UNO R3 Mega 2560 1280 328 UNR The Wiznet W5100 provides a network (IP) stack capable of both TCP and UDP It supports up to four simultaneous socket connections. Use the Ethernet library to write sketches which connect to the internet using the shield With Micro SD card slot, supports SD card up to 2GB, supports 2009, UNO, mega 1280, mega 2560, Nano, Duemilanove Fit For Arduino UNO Mega 2560 1280 328 UNR