This sign is on a bathroom stall door, this stall has a pit. It's basically a hole in the floor so you can...squat.
The entire time my sister and I rationed our fluid intake (in China). No joke!!! When we were in China it was the worst. There were times we saw women coming out of a stall wiping off their legs. It was nasty. Every time we went to a restroom we would cross our fingers, hoping for a sign that read "western style". A few times we decided to wait. Luckily we never had to experience one of these pits.
This one was at Big Buddha. In China rarely was there toilet paper. We would pack some from the hotel. Since visiting China I have a new outlook on our public restrooms. I have no problem using an airplane restroom anymore. :)