I found a small binocular today at the local gun shop. They are made by National Instrument Corp. and are 5x40. The company was in Houston, Texas. They have a fixed bridge, which to me is unusual. They still focus really clearly from about 5 feet to as far as I can see. I did find only one reference to them on another forum. There they think they are WW II. Any info here or best guesses? TIA.