Buffalo WZR-D1800H
From DD-WRT Wiki
Flashing Info
This unit has community dd-wrt build support as of 21061.
Files needed for flashing:
ftp://ftp.dd-wrt.com/others/eko/BrainSlayer-V24-preSP2/2013/04-01-2013-r21153/buffalo_wzr-d1800h
You should be able to flash the MULTI.bin from within buffalo firmware's webgui, please practice all the proper flashing procedures.
Links of interest
Here is the forum link for discussion on this particular buffalo unit:
http://www.dd-wrt.com/phpBB2/viewtopic.php?t=155100
Here is the link to the dd-wrt file server, in which you can use to download newer or older builds.