HIVIZ 1911 Front Tenon Style Fiber Optic Sight with Interchangeable LitePipes Hi-Viz 1911 front sight Fits most wide Tenon 1911's and can be narrowed to fit early narrow Tenon 1911s Utilizes .090" diameter interchangeable LitePipes Sturdy and bright Easy to install 1911 tenon style front sight Interchangeable LitePipes in red and green Tenon style sight fits most wide tenon 1911s Can be narrowed to fit early narrow tenon 1911s HiViz recommends gunsmith installation for all dovetail sights. Due to manufacturing tolerances, some firearms may require additional fitting.