The HS515GM is a ruggedized micro red dot sight with the option of a 2 MOA dot only or a 2 MOA dot with a 65 MOA circle reticle pattern. Employing LED technology, the life time for one CR2032 battery can reach 2 years if left on constantly. However, the shake awake feature also works to extend the battery life. Extra rugged features including a CNC milled 7075 Aluminum housing, pressure tested for submersion up to 30 meters for 30 minutes and a snag free housing design that protects the windage and elevation turrets.Includes:Lower 1/3 co-witness quick release mount with removable spacerClear flip-up lens coversKill flash filterFeaturesShake Awake Motion on with last setting recallParallax free, unlimited eye reliefWaterproofSwitch between a 2 MOA dot & 65 MOA Circle with dot. No re-zeroing required10 daylight and 2 night vision compatible brightness settingsCNC milled 7075 aluminum housing