A Yu was a free reed wind instrument used in ancient China. It was invented by Emperor Ching Yu, but after another emperor took over the popularity declined. The man never actually knew how to play the instrument and was eventually found an imposter. What a scandal!
They are made of multiple pipes of bamboo, each having a free reed also of bamboo.
There is also a percussion instrument called a Yu. It is made from wood in the shape of a tiger with serated teeth. It is played by striking the teeth with a bamboo whisk. Unfortunately I couldn't find a picture.