This is the worst shower UX I have ever seen and I live in the US (no there is no labelling of these anywhere)pic.twitter.com/R703VtAPVu
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Given the angle, I'm fairly sure the middle is temperature. I'm going to guess pressure is on the left, and right switches between shower and bath, or maybe two different shower heads if it's fancy. Of course, I could have left and right reversed.
I think left is probably hot, right is cold, and middle switches between bath and shower, but it could be different from even that.
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