Apple Thunderbolt to Gigabit Ethernet Adapter - A1433 MD463LL/A - Open Box.
The Apple Thunderbolt to Gigabit Ethernet Adapter lets you easily connect to a high-performance Gigabit Ethernet network. Small and compact, it connects to the Thunderbolt port on your Mac computer and provides an RJ-45 port that supports 10/100/1000BASE-T networks.