Leupold VX-3i 3.5-10x56mm CDS Riflescope w/Illuminated Duplex Reticle Argon/Krypton gas blend, which nearly eliminates the effects of thermal shock, and reduces the diffusion of gases sealed inside your scope even more than Leupold's proven nitrogen technology already does A versatile 3:1 zoom ratio erector system that is ideal for virtually any situation Proprietary MST (Motion Sensor Technology) automatically deactivates illumination after 5 minutes of inactivity, yet reactivates instantly as soon as any movement is detected 1/4 MOA precision finger click adjustments for windage and elevation offer absolute repeatability and dependability over a lifetime of extreme use Crafted from 6061-T6 aircraft quality aluminum