Nikon Prostaff 5 Illuminated BDC Riflescope, 4.5-18 x 40mm Features a red or green illuminated reticle with rheostat dimmer located on the side focus knob for easy adjustment Adjustments are made easy with Spring-Loaded Instant Zero-Reset Turrets Made with Nikons fully multicoated optics for maximum brightness and light transmission A quick focus eyepiece allows the shooter to instantly bring the reticle into focus Optimized for use with Nikons Spot On Ballistic Match Technology