The LM-ERDS (LaserMax-Enclosed Red Dot Sight) is a robust fully enclosed sight for mourning on RMR or MOS optics ready pistols. the housing is constructed of aircraft grade 7071 aluminum. The LM=ERDS comes equipped with an industry first external forward-facing light sensor which automatically adjust the brightness of the red dot based on ambient lighting conditions. A RMR and Glock MOS mounting base plates are included.Features:External Forward-Facing Light Sensor for Auto Brightness Management50,000 hour run time on mid settingBrightness settings: 8 Day / 2 NightShake to awakeReticle: 3 MOA Red DotWinadage/Elevation Adjustment: 1 click = 1 MOAOperation Modes: Auto brightness or manual adjustRMR and Glock MOS base plates includedPower Source: CR2032, included