My catalyst into gun smithing was Herman M Boll. He lived a few blocks away from me in Beaverton when the population had just grown to 3400. I assemble from preproduction parts this, his, peep sight invention. A fine sight albeit a little tricky to adjust but once properly installed my crisp young eyes could punch holes on top of each other @ 150 yards. Not for small bores. Mr. Boll received his patent November 13th 1956. Comes with a copy of his patent. Not likely to find another one as I don't know if he sold any. He was a real craftsman but not much of a salesman. I have no heirs. No Idea of value real or perceived, it could be yours for fifty bucks OBO?