It is probably that one, but if you are not 100% sure where the brake fluid reservoir is it's probably best to get someone to show you the first time.
If you have to top it up again in the next few months get the system checked for leaks.
fred, November 2009
DOT 4 is more usual, and mixes perfectly well.
John, November 2009
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I can answer this question...
Do I top up my brake fluid in the container saying use Dot 3 ?