I was facinated to find and purchase a strain made by the Ohio Brass Co. intended for radio use recently. I had a 5 inch version and this is a 10 inch version. I could find very little info on these except for a advertisement from 1923 showing them. They are marked with a nice straight embossing "Ohio Brass Co " and the catalog number. I have yet to find a catalog page showing these and there use. Here are the two I have. The 10" number 26331 and the 5 inch below it number 26330. If anyone has any info on these I'd love to see it.