The Dreamcast LAN Adapter (HIT-300) is a Japanese-only peripheral that connects to the G2 bus in place of the modem and provides the Dreamcast with 10mbps network connectivity. It uses a Fujitsu MB86967 chip, and should not be confused with the more common and vastly superior Dreamcast Broadband Adapter, which uses a RealTek 8139C chip.
The only official software that works with the LAN adapter is the "Dream Passport 2 for LAN" web browser. No official games from any region are compatible with the LAN adapter. Homebrew software that is compatible with the broadband adapter is usually also compatible with the LAN adapter, however, software is not often tested with the LAN adapter explicitly due to its rarity.
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