Wilson Jones Ultra Duty Round Ring Binder with Extra Durable Hinge, 1/2", Black (W87912PP3) (W87912PP3) Get premium features, a higher sheet capacity, extra pockets and the best durability with Ultra Duty binders. Ultra Duty combines our best ring with our strongest covers for unmatched ease of use and strength. Round rings with a Single-touch trigger keep papers secure yet are so easy to open that you can use just one finger. 1/2 round rings hold 120 sheets; D-Lock, spill-free, never-gap rings ensure excellent paper security by closing tightly Features our strongest binder covers and extra durable hinge for years of reliable use; Custom formulated, PVC Free polypro material lasts up to 10X longer than vinyl Multiple colors and sizes available