What's the Japanese for dual flush toilet, a flush toilet that allows you to choose either a large flush (大) or small flush (小)?
Google translate suggests "デュアル水洗トイレ" (katakana for "dual" plus "flush toilet"), but the Japanese Wikipedia article on flush toilets doesn't have "デュアル" in it, nor does the Japanese Wikipedia article on toilets in Japan (a google search for オーストラリアの便所 didn't help, either). jisho.org doesn't have anything matching "dual flush" or any relevant matches using デュアル (and based on this search for dual there's only one katakana form for "dual").
Searching ejje for dual flush toilet just supplied the English language Wikipedia article.
linguee.jp had one match for dual flush: "二重流し水洗トイレ", from Australia's main tourism site.
Maybe there's a semantic gap, because Japan doesn't have many single-flush toilets.