A stem is the part of a watch that is used to control the winding and setting of the timepiece. It protrudes from the center of the watch case and is typically made of metal. The stem has two sections, the upper section called the crown and the lower section called the tube. The crown is used to wind the watch and to set the time. The tube is used to secure the stem within the case. The stem is the main point of interaction between the watch and its user, making it a key component of the watch.
