Adamantine Breastplate of Toughness

This suit of armor is reinforced with adamantine. While you're wearing it, any critical hit becomes a normal hit.  When armor is attuned you gain the "Tough" feat.

This armor consists of a fitted metal chest piece worn with supple leather. Although it leaves the legs and arms relatively unprotected, this armor provides good protection for the wearer's vital organs while leaving the wearer relatively unencumbered.

Notes: Immunity: Critical Hits, Bonus: Hit Points, You gain the "Tough" feat only when armor is attuned, Combat, Warding