KRUGER K4 Series 4-16x40 Riflescope with Side Focus Riflescope with 4x to 16x magnification and 40mm objective lens Rapid Target Technology for easy, split-second target acquisition Fully multicoated optics for accuracy and precision Oversized exit pupil; waterproof and fogproof housing 3.75-inch eye relief; 1/8 windage/elevation adjustments with clicks