Small enough to fit in a shirt pocket, and easily ranges big game animals at over 1000 yard instantly. I even range Prairie Dogs in open terrain at well over 500 yards. I have yet to see an animal that I couldn't range, so I don't know what the practical distance is yet. The LED display is easy to read in any light level. I couldn't be happier with it! The most difficult part is holding it steady enough to hit a Prairie Dog at 500+ yards. I have used several different brands and Leica easily comes out on top.