Bilingual what?

I was looking for a new sewer hose for the rig, and when looking at "sanitation products for your campsite" came across:

... as far as I know, my bathroom tissue has never spoken to me... so I don't know whether it is bilingual or not!

Maybe it is necessary for use with this toilet?

http://www.camco.net/campsite-sanitation

Things that make me go, "huh?"