Patented No.1 mechanism with outstanding closing force for a precise fit every time, guaranteed to work reliably even after 10,000 uses. Perfect fit of the rings even when fully loaded. Replaceable spine label for personalizing your file. Cover fastening rings, pull-out hole and edge protection metal strip for easy use and secure storage of documents. 350-sheet capacity (80 g). 3-year warranty on the mechanism. FSC® certified.