Simple and easy to use wire binding ring. It is widely used for organizing office materials and school essays. Users can choose the color and size of wire binding ring according to their needs. Multi color and black color for you to choose. 0.6 inch (14.3 mm) Diameter: 90 sheets 0.6 inch (15.9 mm) Diameter: 110 sheets of paper with a double iron ring binding. Insert a hole in the paper with a punch wire binding ring and finish binding. Iron ring so you dont have to worry about the quality. No need to worry about the bookbinding difficulty when using with an iron ring binder.