SWAROVSKI OPTIK 5-25x52 dS P Gen II Digital Riflescope with 4A-I Illuminated Reticle (Black)The dS automatically displays the correct aiming point and all the data you need in high resolution and in real time. Hunters no longer need to adjust the rifle scope manually, making it much easier to tackle long range shots. The aiming point is calculated based on precise distance measurement, the angle of fire, the magnification selected, air pressure, temperature, and the ballistic data for your personal firearm ammunition combination. dS