Nikon ProStaff 4-12x40 Black Matte Riflescope (Nikoplex) Compact riflescope with 4 to 12x magnification and 40mm objective lens Fully multicoated optical system transmits up to 98 percent of available light Zero-reset turret with spring-loaded adjustment knob; 3.7 inches of eye relief Nitrogen-filled, O-ring-sealed housing for waterproof, fogproof performance Nikoplex reticle; quick-focus eyepiece; measures 14.1 inches