Zhang and his friend Li went to lunch in a restaurant in Jinan, Shandong province, last Tuesday and ordered seven steamed stuffed buns and a bowl of egg soup.

Zhang was eating one of the buns when he bit into something hard. After a close examination, waiters determined that it was a nut from a bolt. They were not sure how it got into the bun.

The restaurant owner agreed to give Zhang three buns for free as compensation, and Zhang accepted them.