This is the assembly screw Winchester model 61 .22. Also called the take down screw. The only difference between this takedown screw and the 19890/1906/62 is the pin hole is farther in on the threads. The pin that goes through the Forearm of the take down screw when it is in gun is part number p110. This pin stops the takedown screw from falling out of the gun when it is not screwed tight.
