Ironwood Body( Races of Eberron, p. 119)
Your body is crafted with a layer of hard ironwood that cushions blows.
1st level only, Warforged,
Your armor bonus increases to +3 and you gain damage reduction 2/slashing. You are considered to be wearing light armor, and have a +4 maximum Dexterity bonus to AC, a -3 penalty on all skill checks to which armor check penalties apply (Balance, Climb, Escape Artist, Hide, Jump, Move Silently, Sleight of Hand, Swim, and Tumble), and an arcane spell failure chance of 20%.
Unlike most feats, this feat must be taken at 1st level during character creation. A warforged with this feat who then takes Improved Damage Reduction (see page 55 of the EBERRON Campaign Setting) can choose to gain damage reduction 1/adamantine or improve the damage reduction granted by this feat by 2. Unlike the Adamantine Body and Mithral Body feats, warforged druids who take this feat can cast druid spells and use the druid's supernatural and spell-like abilities.
Without this feat, your warforged character has an armor bonus of +2.