Board Thread:General Discussion/@comment-24382631-20140105033403/@comment-26420452-20140106055637

In fact, rather than a definite time limit, there seems to be a fatigue limit. A petal of Daiguren Hyōrinmaru won't shatter because a certain time has passed, rather it's Hitsugaya who's getting tired.

The same concept with the Visored's masks. Mashiro can use her mask for 15 hours when in training conditions, however during a real fight, it broke as fast as any other Visored would have.