I received the letter on my 5 screw pre-29 44 Magnum. See the picture. I wonder if this was sent to a distribution center for Army/Air Force PX's and BX's, or just to one PX. Seems like a large number in the order if all went to just one place, especially since they had just been made available for 5-6 months. If anyone is keeping a list of pre-29's by serial number, please feel free to add this one to your list.