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This shield protects the wielder as if he had the Deflect Arrows feat. A shield with this ability protects the wielder from ranged attacks. Once per round when he would normally be struck by a ranged weapon, he can make a DC 20 Reflex save. If the ranged weapon has an enhancement bonus, the DC increases by that amount. If he succeeds, the shield deflects the weapon. He must be aware of the attack and not flat-footed. Attempting to deflect a ranged weapon doesn’t count as an action. Exceptional ranged weapons, such as boulders hurled by giants or acid arrows, can’t be deflected.