Weapon Specialization
From Talus Wiki
Type of Feat: Class
Prerequisite: Fighter, BAB +4, Weapon Focus (chosen weapon)
Specifics: A character with this feat has trained especially hard with a specific weapon type, gaining a +2 damage bonus when using these weapons in combat.
Use: This feat may be selected multiple times, but the effects do not stack. It applies to a new weapon in each case, so long as that group is already associated with Weapon Focus.
Notes
Another prerequistie for this feat is 4th level in Fighter.