Specifically designed for M-16 and AR-15 rifles, this scope features a built-in bullet drop compensation system that is calibrated to 500 yds. in 100 yd. increments. Its integrated base easily mounts on the inside track of a rifle's carry handle. At the base is a peep sight that allows you to use the rifle's iron sight. Its improved design also features a standard black Mil-Dot reticle, standard windage and elevation adjustments, and fully coated optics. Waterproof, fogproof, and shockproof. One year limited warranty.