Seems it only comes in 3-1/2".
I have some 000, quite a bit of 00 and a couple boxes of 0. But I really like #4. Since I mostly buy 2-3/4" stuff so they can be used in my New Haven coach and my shorty M11, twenty seven 1/4" pellets is more appealing than 8 or 9 of the larger ones.
I suppose I'd give 0000 a try if I had a 3.5" gun, but since I don't.........