The Filofax Pocket organisers we see today are all 6 ring organisers, but at one time they used to be only 4 rings. The change over happened sometime in the 1990's, there was a bit of a consumer outcry at the time, which included the Filofax MD at the time being asked to appear a consumer programme to be interviewed by Anne Robinson, pity the thought... But a compromise was reached and Filofax produce inserts that fit both 4 and 6 ring pockets still to this day.
So how are they different? Read on..
So first here is the current 6 ring page with the rings shown in red.
Note that the holes in the paper are slotted for holes 1, 2, 5 and 6. Each ring is spaced 19mm or three quarters of an inch from the adjacent one.
Now look at the same sheet of paper when used in a 4 hole Pocket.
Notice how the rings have shifted to the bottom of the slots. The rings are still 19 mm from their immediate adjacent neighbours, but rings 2 and 3 are 51 mm or 2 inches apart...
Now the clever ones amongst you will say ah... that sounds familiar. Yes it is, because it is the same as Personal ring spacing.
So the slotted Pocket paper will slot directly in to Personal 6 ring binders in the middle.
If it's not slotted a modern 6 hole pocket page will not fit in 4 ring Pocket without punching new holes or 6 ring Personal or A5 without folding or adding another hole. Where as the 4 hole paper or slotted 6 holes will fit in to personal or A5 organisers.
So if you buy a 4 ring Pocket, you also need a Personal size punch because the hole spacing will be correct when the paper is put in the centre of the punch and just the middle punches are used to make the holes.
NOTE: As from January 2015 Filofax no longer sell slotted inserts that will fit the 4 ring organisers. Although you might still find stocks of slotted inserts in local shops.