Here in Brazil, in many bars when you buy a beer you get another for free (on weekdays, normally in the afternoon)

 

We say it �s "double dose of beer".

 

Is there anything similar in your speaking english countries?

 

If yes, what is it called? If not, how would you say that?

In the UK, that would be expressed as BOGOF (buy one get one free) but that �s not specific to bars - it �s a supermarket phrase, usually. In many bars, we have �the happy hour � although it can last for any length of time, when you get special deals on drinks, mainly earlier in the evening, to attract customers. 

Cheers!