I've looked over a hundred strings and so far I've only found two strings with ONLY the patent date and 3/4 of a string that has no marking whatsoever. Asking $40 per string with only the patent date. $20 on the one unmarked disk I have left. Two of the three unmarked pieces are already spoken for. Strings will come assembled with a hook on top and a loop on bottom just as I found them.

Pic shows the string, the single patent date (almost the size of the double date inkstamp) and then the double date marking (patent/manuf dates) on the more common strings.

I can get some of the common two date strings for those interested. Asking $40 delivered to the Springfield OH in Nov, etc. Thanks for looking. Brian