Steel sight includes a bright fiber optic insert that draws the eye for fast target acquisition. The sight's open center allows for maximum light absorption to produce a brighter aiming reference. Two interchangeable inserts (red and green) are included. Three available heights make this sight compatible with most rear sights. Fitting may be required. Dovetail depth is 0.075".NOTE: When installing the fiber optic rod, use a small dab of crazy glue where the rod will touch the middle support of the sight.