This Remington manufactured longer early variation plug (filler) screw is for the top portion of the trigger guard behind the receiver on the model 12 slide action rimfire rifle where the optional peep sight would be mounted and is in very good condition with light slot wear.  (file photo)

Note: Remington model 12 takedown slide action rimfire rifles with the following serial numbers have been observed with this part: 351695, 356902, 374345, 480368, 575662 & 656863

12-A: 30310 & 374065

12-C: 303506, 408616, 409187, 597770, 600364, 607712, 640490 & 663586