Large quantity: you will get 20 pieces 3 rings loose leaf binders book rings, enough quantity for you to make several notebooks and share with families or friendsRustproof and waterproof: these metal loose leaf binder book rings are made of multi-layer stainless steel, not easy to be broken, featuring good resistance to water and rustFlexible to use: each binder ring is well-designed, can be split into 2 halves and connected with a metal swivel rivet tightly, tight and safe to useFit most books and albums: each ring metal loose leaf binder is about 1.57 x 0.98 inch 4 cm x 2.5 cm) and it's inner diameter is 0.787 inch 2 cm), proper size to fit most books or albums, easy to fulfill your needsWide usages: these metal loose leaf binders can be expanded and closed easily, flexible for you to DIY travel diary, photo album, scrap booking, loose-leaf notebook and graduation alumni book