I also have another couple of Fairbairn-Sykes type daggers, one was a commissioned piece that a very good friend and maker did for me and the other one was given to me by a family member who was having a clear out.
Below right is the dagger that was commissioned by me, on the left is the dagger given to me, this one has no markings that are visible. The cross guard was quite rusted and pitted and after cleaning there are no obvious markings but the dagger does feel solid in the hand and everything is tight.
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