fetch vs iron armor

I got an arm between the fetch and my neck. It couldn't rip its way through the duster, but it was stronger than it had any right to be. I was lying mostly on my back and had no leverage. It wrenched at my arm, and I knew I only had a second or two before it overpowered me, threw my arm out of its way, and tore my throat out.
I reached down with my other hand and ripped my duster all the way off the front of my body. Cold iron seared the nightmare cat's paws in a hissing fury of sparks and smoke. The fetch let out another shrieking yowl and bounded almost straight up.


Proven Guilty Chapter 35, Page 286