The ODROID H2/H3 Net card brings 4 additional 2.5 GbE Ethernet ports for an incredible low price. It is compatible with the H2, H2 rev. B, H2+, H3, H3+. Using a H2+ you end up with a total of 6 x 2.5 GbE Ethernet ports. With the H2 and H2 rev. B you get 2 x 1 GbE and 4 x 2.5 GbE Ethernet ports.

The ODROID H2/H2+ with the ODROID H2 Net card brings new capabilities and applications. Examples (non-exhaustive list):

Implementing a DIY router or gateway for up to 5 (H2+) clients at 2.5 GbE speed on each port.
Setup a DIY server, e.g. a NAS, for up to 6 (H2+) clients at 2.5 GbE speed on each port.
Brings 2.5 GbE Ethernet connectivity to the H2 and H2 rev. B boards making them able to talk at full speed (usually 2.35 Gbits/sec) with H2+ boards.