Every year appaers the supplement Switzerland special sheet, Bundesverfassung, Tolkien, Disney, this contains the sheets for the Leuchtturm preprint album.The sheets have SF mounts and an 13 ring perforation for the Leuchtturm ring binders.
Here you can store the sheets issued in the previous year.
On all sheets there are frames where you can put the sheets, usually with a picture of the sheet itself. On all these frames are transparent mounts to safely place your sheets in.
The supplement Switzerland special sheet, Bundesverfassung, Tolkien, Disney contains the year 2023