Fracture

 
Prerequisite(s): Base Attack Bonus 2+, Improved Sunder, Power Attack
 
Benefit: When attacking an object with hardness greater than or equal to that of your weapon, you gain +2 circumstance bonus to damage. When you are attacking an object with hardness less than that of your weapon, you gain a +5 circumstance bonus to damage.
 
Source: Mongoose Ultimate Feats