You are skilled in combining your shield bash attack with an armed strike. When you use your shield in unison with a weapon, your training allows you to score telling blows with both.
Prerequisites: Shield Proficiency, Improved Shield Bash, Shield Specialization.
Benefit: When making a shield bash and armed strike attack as part of a full attack action, you take a –2 penalty on each attack. These penalties replace the normal ones you incur for fighting with two weapons.
Special: A fighter can select Agile Shield Fighter as one of his fighter bonus feats.
Source: Player’s Handbook II, page 74.