The Trijicon SRS (Sealed Reflex Sight) represents the highest level of performance from a sealed reflex-style sight. Because of its innovative design, the SRS takes up less rail space while maintaining the durability expected from Trijicon. The shorter housing eliminates the tube-effect typical of other sealed reflex sights. Featuring a large 28mm aperture, the Trijicon SRS provides a massive field of view for quicker target engagements. The 1.75 MOA dot is small enough for precision and with 10 brightness settings it can be bright enough for any speed. Finally, the Trijicon SRS features dual power sources an innovative solar cell assisted by a single AA battery. The SRS01 also includes: Thumbscrew Mount LensPen Logo sticker Manual Warranty Card Scopecoat Specifications: Magnification 1x Objective Size 38mm Bullet Drop Compensator No Length (In) 3.75 in. Weight (oz) 15.1 oz. with Mount and AA Lithium Battery Illumination Source LED Reticle Pattern 3.25 MOA Dot Day Reticle Color Red Night Reticle Color Red Bindon Aiming Concept Yes Adjustment @ 100 yards (clicks/in) 1/2 click per in. Mount Comes With AC32001 - Colt Style Thumb Screws Housing Material Forged Aluminum Batteries (1) AA Alkaline or Lithium Battery ApplicationsLaw Enforcement carbines, rifles, shotguns and submachine guns