SRD:Amulet of Epic Natural Armor

Amulet of Epic Natural Armor: This amulet toughens the wearer’s body and flesh, giving him or her an enhancement bonus to his or her natural armor of +6 or higher, depending on the type of amulet.

Caster Level: 20th; Prerequisites: Craft Wondrous Item, Craft Epic Wondrous Item, barkskin, creator’s caster level must be three times the amulet’s bonus; Market Price: 720,000 gp (+6), 980,000 gp (+7), 1,280,000 gp (+8), 1,620,000 gp (+9), 2,000,000 gp (+10); Weight: —.