Lasts 5:30 at 450 Summoning Magic Skill.
Enough for most zerg fights that you don't want to waste alex on. With the new buffs to minne and protect, this will be more potent anyway, since 10% of 450 (Avergae DD with pro V) is only 45, but 10% of 600 (average DD with new pro V) is 60. In the whm threads, a PLD managed to get ~2300 def without SR. It would give an extra 230 in this case^^