The increment choices refer to the meter selections.
10-300: The smallest yardage meter would be 10 yds at 100% and the largest would be 300 yds at 100%.
Generally, there are two meter choices in putter selection.
10, 20, 50, 100, 150 and 300. and
15, 30, 60, 100, 150 and 300
One is no better than the other, it just depends on personal choice. Some people find it easier with the 10, 20, 50, etc. The first putter I purchased had only the 15 - 300 and, as a result, I have always played with that meter selection as it is what I am used to and most comfortable with.