The Elcan SpecterOS optical sight is lightweight with rugged 3x or 4x magnification designed for modern military and security applications. Incorporating an illuminated reticle with range finder and proprietary Rapid Aiming Feature, the Elcan SpecterOS combat sight has the unique ability to offer rapid engagement in CQB applications while providing precise aiming at distant targets. A one-piece aluminum housing coupled with shock-absorbing rubber bumpers enable the sight to withstand the severe stresses of modern combat operations. The device can be supplied with either a ballistically-calibrated reticle or calibrated external elevation and windage adjustments and may be mounted directly to flat-top receivers or M16/AR15 handles.