A few years ago I was trying to sort out some parts - picture show three, that are not the same. The one on left has a "centered" loop and the tapered holes for the attachment screws are bigger than the other two - so I am pretty sure that is for a No. 4 rifle. Not much difference I could find on this side of the other two except the lower one on the right has what is likely a British Broad Arrow showing, so I was thinking that made it for a No. 1
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The top one on the right had this "R" on the back - the other one (with the Broad Arrow on front) had nothing on back. I have another with an "E" back there - so, Remington and Eddystone. Without seeing an eagle head mark, I have no way to know if they were for a P14 or an M1917 - all three makers "E", "R" and "W" made both rifles and this part would be identical except for the inspection or acceptance marks.
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