FastFire RD (Rifle Dot) features a 2 MOA red dot - AAA battery offers extended battery life - Fits Weaver-style/Picatinny rails - Brighter dot - Rugged alloy housing is impact resistant - Description: 2 MOA Red Dot - Reticle Color(s): Red - Clear Objective Lens Diameter: 35.5 mm - Finish: Matte - Mount: Picatinny - Eye Relief: Infinite - Click Value: 1 MOA - Elevation Adjustment Total Capability: 90 MOA - Windage Adjustment: 90 MOA - Length: 2.8 in. - Weight: 6.4 oz. - Battery: AAA