I just bought a MKII - MK512 and the rear sight is missing the very small screw to the left of the elevation adjustment screw. What is the function of this screw and should I replace it? TIA, Lacey
This looks like the one you need--2 bucks but you need to order some other parts since a lot of them are just 2 bucks and shipping remains at 6 bucks (even for one item) :)