This +1 weapon resembles a massively oversized spiked gauntlet; one designed for a Medium warforged looks like a gauntlet designed for an ogre. It attaches to the arm of a warforged, completely covering the hand. This component only operates when attached and locked in place.
A battlefist increases the damage dealt by the character’s natural slam attack to 1d8 points of bludgeoning and piercing damage (assuming a Medium character). Versions with higher enhancement bonuses are not uncommon.
A warforged monk who uses a battlefist deals increased unarmed damage as though the character were one size larger than actual, and he can add the battle fist’s enhancement bonus to his unarmed attack and damage rolls.
Faint transmutation; CL 3rd; Craft Magic Arms and Armor, bull’s strength;
Price 2,600 gp; Weight 6 lb.
Source: Eberron Campaign Setting