Suede Collection 9-Pocket Premium PRO-Binder: Sapphire - Rules of Play says:

Zippered PRO-Binder with embossed middle black web material to give cards a classic framed look. Side loading pocket design to prevent cards from easily falling out. Zipper holds the binder shut when not in use. All materials made from archival-safe, acid-free non-PVC material. Holds 360 cards in Ultra Pro Deck Protector sleeves.