Abstract: A device for expanding the circumference of a ring shank includes: (a) an expansion unit movably attachable to an inner surface of the ring shank; and (b) a single hinge pivotally attached within the ring shank about opposite the expansion unit; wherein the expansion unit includes a first, hollow tubing section, an expansion pin or shaft having a first end portion mounted in the first tubing section, and a second, hollow tubing section slidably supporting an opposite, second end portion of the expansion pin or shaft. Also included herein is a ring comprising this ring expansion device. A method of installing a ring expansion device in a ring is also included.