Wirebound

Wire binding is known by a number of different names like ring wire, metal wire, spiral, wiro, twin loop wire.
Wire binding is probably most popular binding option today. There are number of reasons behind this well deserved popularity. Looks beautiful, reliable and favoured by professionals. Wire binding is allowing 360 degree page turn, it means, you can open your document completely flat or folded back on it self.
While wire binding is one of the greatest options, if strong pressure applied on wire, it may bend. They are not as stacking friendly as fastback or hard case bindings.