If your part is like the one in this photo to the left, from an 8531- ll or lll, not sure which now, and your screw is in the middle of the white part behind there in the photo, then the white part circle says 25M16V Type 701, 12vDC .480A, Max press 1/2 PSI
The screw is in what looks like three washers stacked with all of the three showing equal depth, and the screw driver slot in the top of the screw is about 2/3 the way down in depth towards the top of the top "washer"
Sorry the photo does not show where I am trying to explain, but that's what I have.
