Superior Fortitude (3.5e Feat)
From D&D Wiki
Superior Fortitude [General]
+2 to fortitude saves, re-roll failed fortitude save 1/day.
Prerequisite: Great Fortitude, Character Level 6th
Benefit: You gain an additional +2 to fortitude saves, this bonus stacks with Great Fortitude for a total of +4 to fortitude saves. You may also re-roll a failed fortitude save 1/day.