People in Germany are used to finding free postcards in bars and restaurants. But those cards were shaped and labelled like real blood bottles. Filled for the first time with a liquid: artificial blood. It’s no surprise that people in bars were taking a closer look, seeing something like a blood bottle in a dispenser for free postcards.

Blood donations are a serious matter. And it’s hard to convince people of the necessity within seconds. But all postcards have been collected from their dispensers within hours, taken to the people's homes where they can take their time to think about it.