The air we breathe is not as clean as it once was. And in many cases, it is getting worse.

On high-smog days in Krakow, Poland, the city’s air pollution can reach six times that of safe levels. And in the United States, about four in 10 people live in counties that have unhealthy levels of either ozone or particle pollution, according to the American Lung Association.

To help clean up the air, Dutch designer Daan Roosegaarde created a 23-foot-tall air purifier called the Smog-Free Tower in 2015. Now, he’s installing a tower at Jordana Park in Kraków, where it will stay from 16 February to 15 April.

The tower-like device essentially sucks up smog from the top and then releases the filtered air through its six-sided vents. It can clean more than 30,000 cubic meters of air per hour and uses no more electricity than a water boiler, according to Roosegaarde.

His firm Studio Roosegaard calls the tower the world’s first “smog vacuum cleaner.”

The project, which was funded on Kickstarter, took about three years of research and development, but Roosegaarde was finally able to show off his massive machine in September 2015 in Rotterdam. In 2016, Roosegaarde’s team partnered with the Chinese Ministry of Environmental Protection to take the giant air purifier on a tour of four Chinese cities to help clean up the air.

According to Roosegaarde’s website, the air purifier was specifically created to be used in public parks as a local solution to air quality, so it will likely be spotted in public parks as it makes its way around the country.

Roosegaarde describes how the tower works in more detail on the project’s Kickstarter page:

“By charging the Smog Free Tower with a small positive current, an electrode will send positive ions into the air. These ions will attach themselves to fine dust particles. A negatively charged surface – the counter electrode – will then draw the positive ions in, together with the fine dust particles. The fine dust that would normally harm us, is collected together with the ions and stored inside of the tower. This technology manages to capture ultra-fine smog particles which regular filter systems fail to do.”

The air purifier doesn’t just clean up smog, it can also be used to make fine jewelry.

The fine carbon particles that the tower collects can be condensed to create tiny “gem stones” that can be embedded in jewelry pieces like rings and cufflinks. Each of the tiny stones is the equivalent of 1,000 cubic meters of air.

Roosegaarde aims to eventually take his tower to Mexico City, Paris, and Los Angeles.