Trijicon AccuPoint 5-20x50mm Rifle Scope provides shooters the ability to accurately extend their range in any light. Advanced fiber optics and tritium aiming point illumination speeds target acquisition and extends available shooting hours Dual-illumination system automatically adjusts aiming point brightness to existing lighting conditions Manual brightness override allows shooters to easily adjust the reticle to suit their preferences 30mm tube offers a greater range of mounting options Rugged, aircraft quality, hard anodized aluminum body offers all weather protection Unmatched long eye relief protects against the recoil of higher caliber rifles Easy to use external turret controls for windage and elevation adjustment Side parallax adjuster for enhanced accuracy at a long range