Amazon.com: HiLetgo W5100 Ethernet Network Shield W5100 Ethernet Expansion Board with SD Card Slot for Arduino UNO MEGA2560 : Electronics
Ethernet Network Shield 5100 For Arduino UNO - Makerguides.com
Mini W5100 LAN Ethernet Shield Network Board Module Ethernet UNO Mega 2560 3.3V Geekcreit for Arduino - products that work with official Arduino boards