The Pince-Nez style was popular from the 1880s until the 1940s. There are two types of Pince-Nez frames and many variations within each type. The kind below have a spring bridge that serves as both a bridge and also to provide the tension that keeps the frames on the nose. Generally, it is easier to adjust the spring bridge type for fit. The spring can be bent in or out to increase or decrease the bridge width.
Learn more about Pince-Nez styles and fits here.