I used to have a J flag, but I remember it was bigger than 2 ft wide ... with the luff cut at a diagonal so it flew straight off the forestay. 30 x 24 30 ft off water isn't really a major statement. US flags minimum to look OK are 3x5 ft.
So if we fly it at spreader level ... say under power I wonder how much width it would take to still be clear of the mast?
And I think it used a #6 luff tape to slide into foil
as one of those pictured seem to be.
[this was before I got roller furling ... so I wouldn't opt for the luff tape with a furler, but it does fly a lot better locked into the foil.]
