Designed by the professional shooters, combines passive rangefinding with MIL Dot marks for estimating holdover up to 13.5 milliradians (mrad or mils) at vertical line and 7 milliradians at horizontal line. Each grid is 0.5mil, Diameter of dot is 0.2mil. Using this passive rangefinder with the known ballistics of the weapon and ammunition makes for quick, accurate shots.