Ultimate+ Weapons
Ultimate Weapons+, indicated with /U+ at the end of the Weapon name, are end-game top-tier weapons that have special bonuses such as large PA Damage boosts, added or increased SE infliction rates, weapon range, and more.
Ultimate Weapons+ can be found as Clear Box item drops in Ultimate Difficulty Missions, from certain Ultimate Level Enemies, or can be acquired by awakening /U weapons via crafting a board in your room! You can buy these boards from the Exchange Shop.
(As a side note - you can NOT grind or repair these weapons using Guardians Cash, but you can still use GC to change the element).