Built to meet the demands of professional precision shooters"" the FDN 25X offers everything a shooters needs to push their rifle's limits. The FDN 25X features a reengineered optical system to guarantee the sharpest image resolution possible throughout the 5-25 magnification range. Target acquisition for accurate shots beyond 2""000 yards is facilitated by the rapid adjustable 180 degree magnification throw. The ER3K elevation knob provides the shooter with the ability to perform eleven mils of correction per one revolution. The FDN 25X 5-25X features a 52mm objective"" 6061-T6 aluminum 34mm tube"" low-profile ER3K elevation knob with a zero stop"" ergonomic capped US#1 windage knob"" integrated illumination and parallax knob"" rapid adjustable 180 degree magnification throw"" and customization options that will undoubtedly meet your needs.