Effect of this item is only 60 seconds, giving an additional 3MP per tick, for a mere total of 60MP.
However, a noteworthy trait about it, is that it seems to actually stack with other sources of refresh, such like Yagudo Drinks, etc.
Keep in mind, that you may switch the Refresh Musk out, with other non-expendable ammo items, such like the Bibiki Seashell, which will NOT result in TP reset. But equipting this, while wearing a ranged weapon, will reset your TP to 0, as it will unequipt your ranged weapon.
Like other charged gear, there will be a few seconds cool-down delay after usage, that disallows casting, using job abilities, as well other items.