Nikon ProStaff 3-9 x 40 Silver Riflescope (BDC) polymer Imported Compact riflescope with 3 to 9x 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; 3.6 inches of eye relief Nitrogen-filled, O-ring-sealed housing for waterproof, fogproof performance BDC reticle; sleek silver finish; measures 12.4 inches