3.6 MOA in a MiL. But that chart has me confused. It's seems way too complex haha. I don't understand the "Fine Vertical Post Height" list they have there. But what it looks like, for windage, each little line is the equivilant of one mil-dot and then the numbers aid you for quicker adjustments. Not sure what kind of hurricane you would be shooting in to have to adjust for 20+ mils but whatever. The 1 MOA might be throwing you off, it did for me at first, don't worry about that other than it's going to cover one inch at 100 yards.

This optic wont help you with range estimation unless you flip the rifle on it's side to measure height. But the "19 inches at 25m" means that if a guy fits to those lines shoulder to shoulder he's 25 meters away. If you could fit two guys in there, 50 meters etc.

Lastly, if this is a variable power optic these marks are only good on full power.