Iron Heart Leather Bag Black This bag is made of leather with a textured grain, and while the details are unclear, the leather quality feels similar to deerskin. (Although it's probably cowhide) To compare sizes, I've stuffed the bag with newspaper and placed a Kuroyoroi mini bag next to it. (The Kuroyoroi bag is not included) There is some wear and tear, with some scuffs and scratches, but it's generally in clean condition.