Picked up a shoebox full of 1911 parts yesterday and I found this inside. It appears to be a wartime Ithaca GI slide. The only markings are the flaming bomb under the firing pin retainer and the P on top in front of the rear sight. Obviously the sides have been polished, it has been reblued, and the front sight has been replaced. What is the cut out with the two screws in the left side? I can find nothing online about this and I have no idea. Am I correct in thinking it is an Ithaca? What do I have here? Thanks for any info.