While living in Argentina, I encountered a type of window blind system there called a "persiana." It looked like this:
You tug on the nylon belt to the right to raise and lower the blinds, which are usually made of plastic. There are holes between the slats to let the air through without letting in lots of light. They are notorious for being difficult to operate and breaking often, as this one here (the case is missing, probably because we were trying to fix it).
Is there a word for this kind of blind system in English? I thought about "louver" but that doesn't seem quite right (according to Google Images/Wikipedia).