Target game as well at dusk as at midday with the Vortex Viper riflescope. XR optics coatings give the Viper an impressive 95% light transmission for a bright image in even faltering light. Accuracy matches image brightness with pop-up windage and elevation dials that adjust in audible 1/4 MOA increments. The fast focus eyepiece is topped with a ViewMag Adjustment Bar to help you keep track of the scope's magnification setting and your target easily. Waterproof and fogproof performance guaranteed thanks to Vortex's argon gas purging. One-piece aircraft grade aluminum tube construction. Enjoy a constant reticle image thanks to second focal plane reticle placement. Factory tested 500 times under a force of 1000 G's. Black finish. Manufacturer's lifetime warranty. Side Parallax Adjustable models allow you to adjust parallax while maintaining your shooting position. Vortex Viper Riflescopes feature: XR lens coatings for 95% light transmission ViewMag Adjustment Bar Argon gas purging for waterproof and fogproof performance 1/4 MOA windage and elevation adjustments Fast focus eyepiece FOV = Field of view at 100 yards