Lot of 24 WWI Era 6th Infantry Regiment Enlisted Collar Discs with screws

Description

This listing is from a collection of military memorabilia.  I cannot verify authenticity, but I will include what I have been able to discover, if anything, in the listings.  Dates and locations, when given, are best guesses according to notes and research. Condition is "as is" - please see pictures.  I am reluctant to try to "clean" anything for fear that it could instead damage some of the pieces.
If you have any questions, please ask - I will try to answer as best I can.  The items were in a smoker's home, so some of the pieces may have a residual smoke odor.
This listing is for a lot of 24 6th Infantry Regiment Enlisted Collar Discs.
They are World War I Era
All are marked on the back with A. E. Co, Utica, NY
All have the screw nuts.
Please see pictures for details.
Items will be shipped in envelopes; First Class Mail (large Envelope),costing .00, flat fee for domestic shipping.  Shipped within 2 days of receiving payment through Paypal.
Thanks for looking!