Summary: Though I am not in the forestry field, either for work or play, I settled on this model of laser rangefinder because of its hypsometric capabilities. I've been using the Nikon Forestry 550 Hypsometer Rangefinder to establish the heights of various buildings, antennas, bridges, and cliffs. And because I wouldn't always have the time to do the geometry calculations on my own, I settled on this model, with its built-in understanding of Pythagoras' elegant formula.
Summary: Pro: Compact, light, relativity inexpensive, waterproof Con: Uses 2-point height measurement method If this unit used the 3-point method of other range finders, it might be close to perfect. As it is, it is only useful for open grown stands. You must have a CLEAR view of both the top and base of a tree or you get faulty measurement. With either brush around the base, or branches between you and the top and it's useless.