The Barska 4x20mm Electro Sight Carry Handle Base Mil-Dot Rifle Sight with BDC Turret by Barska is specifically designed for M-16 & AR-15 Rifles. It features a built-in bullet drop compensation system calibrated to 500 yards in 100 yards increments. The Integrated base easily mounts on to the inside track of a rifle's carry handle. At base of the integrated mount is a peep sight that allows you to use the rifles iron sight. Featuring a Mil-Dot reticle, included lens caps & lens cloth, and fully coated crisp optics. FeaturesIntegrated Carry Handle Mount (Compatible with M16 and AR-15)BDC TurretIncludes Lens Covers