A card that has the 
Awoken Assist awakening; weapon assists are almost exclusively used as assists and not as subs or leaders. A weapon assist passes on its awakenings to the card it is assisting, as well as its active skill. The weapon assist can also pass on a portion of its stats if the main attributes of the assist and the base card are the same. See Assist for more information.
Weapon Assist
Or Equip
Japanese: アシスト