Recently acquired this item and have never seen another. I know it's made by Ohio brass, is patented in 1901 and is some sort of a spool. I would like to know how it was used, could it be a MINE insulator?, has any one ever seen a pin for it? Lou Hall? approximate value? There are two more pix, plese take a look and let me know if you have any ideas. THANX

Quick replys identifies this as : King's patent # 667,882 Mine insulator