Mana Black Tungsten Koa RingMana Koa Wood Black Tungsten 8mm Ring Mana means strength and power in Hawaiian and this ring embodies both. Our Mana Koa Wood Black Tungsten Ring combines the strength of Tungsten Carbide with the power of the mighty Koa Wood tree. The combination of the two form a stunning but simple design! If you want a ring that stands up to just about anything, this is the one at an amazing price! Tungsten Carbide one of the strongest metals in the world Koa