New version fits 3.1in LOC/standard tubes. I'll definitely try out designing a 3 fin version with slightly longer root end.Oh! No issue, as I am sure I could fit a mailing tube. Being a 3D print, these are probably better suited for paper tube anyway. It was just that filament fiberglass was all I had on hand to try it out on.
For that matter, a lighter 3-fin might be acceptable as well, possibly with a slightly longer root end (?)