WW1or WW II Engineer Collar Disk "D

This is a WW1 or WWII Engineer Uniform Screwback Collar disk.I beleive it is WWI, but possibly WWII,the reference tag on it says 14M9 D 248, I don't know anything more about it. It is in Good shape, with the back holder on it.This is from an old family collection.

Payment must be received within 5 days of winning bid. I am very happy to combine shipping on multiple items for seven days, just let me that you are still bidding, I can revise your invoice. I can mail this First class if you like,I can't take responsibility for it after it leaves me.
I accept PAYPAL,if you send a money order please send a postal money order. I do not accept personal checks. T is an additional $1.00 fee for delivery confirmation & handling included in postage. I ship as soon as I have clear payment.

Thank-you for looking !! Please

e-mail me with any questions.