These twist lock rings are a convenient and secure way to organize your floss bobbins. The rings are made from stainless steel wire coated in pretty colors. Each wire ring has a screw lock that holds the ring tightly closed so they won't accidentally open like other bobbin rings can. The rings come in a set of 6. Each ring has a diameter of approximately 2 inches when closed. You can also screw two or more rings together to get a larger circle.