An exquisitely crafted sandalwood puzzle box made by Pei Jingheng as Pei Lingrong's coming-of-age gift. It features a wooden latch and four small raised buttons at the corners of the lid. The mechanism is based on the Five Elements principle—the correct pressing order is upper left, lower right, upper right, then lower left. Pei Lingrong could only partially open it but could not fully unlock it. Shen Yunshuang successfully solved it.
