Belgian-made, exposed hammer, underlever side by side double. The rollmark on the rib seems to imply that it is a 10 gauge. Definitely pre-1915, it is missing the forearm and seems to be in only fair condition, and it might be proofed for black powder. As much as I hate to say it, I agree that this one should probably be a wall-hanger unless you have some reason to put money into it. Value $100 or so for curio.