This kit includes the sealing plate and proper screws needed to mount an RMR®/ on the Glock® MOS slide and the Springfield® OSP pistol. For the SRO™ only the screws in this kit are required for proper mounting. See "When to use the RMR Sealing Plate" in FAQ. The AC32064 kit includes:1 - RMR Sealing Plate2 - Optic Mounting Screws (short)1 - Hex KeyNOTE: One must have this kit to mount an RMR®/SRO™ on a MOS slide. RMR®'s and SRO™'s ship with two long screws which will NOT work. You will need the two short screws in this kit Trijicon RMR® Footprint Mounting Kit - Fits Glock® MOS, Springfield® OSP & Prodigy™ , Walther® PDP, and H& K® VP9 Optics Ready AC32064