The RMSw is designed to resist damage from water or other harsh environmental conditions. The RMS-W is gasket sealed to create a watertight fit between the slide and the battery compartment without the need for additional mounting plates. When the sight is mounted it will remain watertight at depths of up to 20 meters for over 30 minutes. The RMS-W also features a newly designed frame which adds thickness to the housing as well as a new side profile. The RMS-W will also be the first sight in the RMS line to benefit from the newly developed hard coated polymer lens. The RMS-W has the same footprint as all previous Shield mini sights and will fit any slide that h Mfg: Shield Sights Ltd.