It comes in the screw kit
pin set 1
screw 1A
Sealing plate is not required to make the RMR type 2 to function. If you want added water submerging protection, then use the sealing plate. If the cut on the slide is completely solid, you don’t need the plate since the slide will seal against the slide. But on slides with multiple screw holes like the Echelon, some of then are deep enough to open up into the internals. If you submerge the pistol water can come though the slide and up under the RMR so a sealing plate helps Seal all the water egress points. If you have the extra disposable cash why not? If you don't plan on diving with your pistol not needed.
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