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PA Fragment
PA Fragments are unique items that can be stacked up to x99, and are given as a reward for completing free missions at S-rank difficulty with a rank of 'S,' on top of the original meseta and mission points/class experience. These items as well as the prizes that can be bought with them can not be traded or sold to other players. However, one can transfer them from his or her own character to another character on the same account through the player's shared bank.
While the description reads: Becomes a target for enemies and defends allies for a set amount of time, these items are used to purchase "Ultimate" Photon Arts in a quest which has yet to be released on the PSU US servers. These Ultimate Photon Arts are not purchasable from NPC shops, nor are they purchasable from Player Shops.
NPC shops will buy PA Fragments for 100 meseta.