4 Used Original Sega Internet Modem Adaptors for Sega Dreamcast. The Dreamcast Modem Adaptor brings gaming to a whole new level! Plug it into the Sega Dreamcast console for dial-up online access. Used Original/Genuine Sega replacement parts for Sega Dreamcast. These Modem Adaptos are in very good to excellent condition and include a 30 Day warranty. Includes ONLY the modem units as pictured, no other cables or instructions are present.