Unfortunately, that answer is incorrect. This is a multi-entry visa which allows three utilizations of a base of 60 days. All entries (as long as they have not yet expired) are capable of being extended an additional 30 days.

(I am leaving incorrect information here so that readers can see how I was corrected below)

So far I have not seen anybody else post the correct answer with explanation here.

Your multi-entry Visa allows you unlimited entries with a max duration of 60 days each for a period of 6 months from your first use of it. As long as you go into the immigration office before that 60 days ends you are capable of extending each stay by another 30 days.

Additionally, and each calendar year, most western countries are allowed three fly-in 30 day automatic entries, and two walk in 30 day automatic entries. Each of those can also be extended by 30 days if you go into the immigration office before they end.

Your multi-entry pass will allow you (with optimum utilization) 9 months, and if you choose to use your automatic entries, you might be able to wiggle another 14 months if you time it right in the calendar. (The auto entries apply in any calendar year and renew each year)