See also: Feats
You are adept at fighting with two weapons and double weapons.
Prerequisites: Dexterity 13, Base Attack Bonus +1
Effect: When you attack with two weapons, or with both ends of a double weapon as part of a Full Attack Action, you take a -5 penalty (Instead of a -10 penalty) on all attack rolls until the start of your next turn. You only gain this reduced penalty if you are wielding a weapon with which you are proficient.
Normal: If you use a Full Attack Action to make more than one attack on your turn, you take a -10 penalty on all attack rolls for the round.
Additional Dual Weapon Mastery I Effects 
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Reference Book: Star Wars Saga Edition Starships of the Galaxy
Vehicle Weapons cannot be used in one hand, so this Feat has no effect on them.
Reference Book: Star Wars Saga Edition Knights of the Old Republic Campaign Guide
Combined Feat (Quick Draw): You can draw or holster two weapons with a single Swift Action; you must have both hands free to draw both weapons, and each weapon must be able to be held in one hand.
