The built-in rangefinder uses a class 1 eye-safe IR laser to measure distances from 10 to 1340 meters. You can range to a stationary target in single-distance mode, or use the scan mode to track moving targets or to quickly measure multiple subjects. The rangefinder has a built-in inclinometer that measures the up or down viewing angle, and calculates and displays an adjusted horizontal distance that can assist you in ballistic compensation calculations. This model displays ranges in Meters only, and it cannot be changed.