Heavy-duty binders feature an extra-durable hinge and are made of custom-formulated, PVC-free polypropylene. Polypropylene binders last up to 10x longer than vinyl binders. Built to last, these binders feature three never-gap D-rings for secure and snag-free paper storage. Binder has four interior pockets. Binder Type: Ring; Binder Style: Non-View; Binder Size Capacity: 4"; Binder Sheet Capacity: 750.