The single adjustable rear sight which easily fits the most popular auto pistols without replacement of the factory front sight. By replacing the factory rear sight with a tpu, adjustable in windage and elevation with hardened click screws, you will convert your semi-auto into a modern firearm ready for target and practical shooting. Vigiliant - Fits .285" rear sight dovetail. Sport - Fits .375" rear sight dovetail. Features: Works with the factory front sight. Fits the existing dovetail slot without milling work. Machined from solid steel using state-of-the-art cnc milling. Tapered dovetail for a better locking in the slide (install from left Mfg: L.P.A. Sights