This is a Super Grade swivel base stock nut for the front swivel base.
Original parts are factory Winchester pieces in excellent condition.
Reproduction parts are new with an external dimension identical to the original Winchester part. The thread is different, however. These reproduction swivel base stock nuts will only work with the reproduction swivel base screws found HERE
We use the NRA Modern Gun Condition Standards Grading System for grading part conditions. You can read about it HERE