The number on the machine is a peak figure that assumes standard copy paper, so card and coated stock count for more than one sheet each. Working at half the rating keeps the pins straight and the holes aligned, which is what matters when the punched stack has to mount on a ring mechanism. Check the centres match your binders. See paper punches, paper drills and binders.

Heavy duty paper punch on a modern office desk with punched documents, binders and filing supplies for bulk document preparation.
Heavy Duty Punches for Filing

Shop heavy duty punches for bulk paperwork, reports, manuals, records and office document filing.