These blue goldstones are 6 mm. The 24-gauge wire has a brass and copper core and is silver-plated with a tarnish-resistant coating. You are purchasing ONE RING. There is one each of these sizes 4–15 of these rings. The ring you see in the picture may or may not be the one you receive. The rings are ready to ship at the time of purchase. These are not adjustable. I can make more of the sizes shown, so please contact me with any special circumstances. Michaels - Rings - 013