New Graduated Blue Ring Mandrel. This is a new graduated blue ring mandrel. This is an essential tool for the jeweler, goldsmith, silversmith and metal worker. This elegant colored metal ring stick can be used to determine the size of rings. Has sizes 1 to 15 in 1/4 size increments by US standards and sizes 13 to 24 in millimeters. Also has 1 - 36 & 41 - 76 universal sizes on the back. It measures approximately 9 7/8" (250 mm) long. We work hard to update our descriptions and pictures of our merchandise. As part of a process of ongoing innovation by our suppliers, newer versions of the item shown may be shipped before we are able to complete an update. As a result there may be a slight variation in color and design.