Tesla today shared details of how effective its particulate filters are. Spoiler alert: They are so good, not only do they clean up the air inside the car, they make the world outside the car cleaner, too. It may not be obvious why this matters: The company is aiming squarely at a very specific type of customer, which may be the company’s way into markets like China and India.

Let’s be frank for a second: Cabin air filters are nothing new; they’ve been rolled out in luxury cars since the late 1970s, and across a broader number of vehicles from the mid 1980s onward. HEPA filters in cars are more novel, not least because for this level of filtration to work, the car must be pretty air-tight to begin with, which traditionally hasn’t been a priority in automotive design.

It’s hard to see adding HEPA filters in the first place, but can adding a layer of one-upmanship on top of that with a Bioweapon Defense Mode button be seen as anything other than a spectacular PR stunt? What nobody seems to have done so far is ask why Tesla is making such a big deal out of it.

The Tesla blog post offers some hints of the most obvious kind. Talking about bioweapons is a way to catch the headlines (just look up there! I fell for it, too!), but the real talking point is that by using industrial-grade particulate filters, the Tesla Model S and Model X are spectacularly well-suited for use in environments where pollution is off the charts.

Of course, the current Tesla models are a lot of things, but one thing they ain’t is cheap.

Put the two together, and you get a Venn diagram of Tesla’s target audience here: People who have access to significant amounts of money and who suffer from tremendous amounts of pollution.

Pollution is a global problem not equally distributed

Around 7 percent of the top 1,000 most-polluted cities in the world are in the U.S., which is the first piece of the puzzle: Creating cars that are particularly well-designed for your home market is just common sense — especially if you’re an electric car company who inherently has a horse in the race when it comes to making a statement about pollution.

Looking at the rest of the data is far more interesting, however, and offers some clues as to why this matters to the car manufacturer: India, China, Turkey, France and Germany all feature heavily in the top 1,000, and, while not all markets are equally affluent (average GDP per capita varies wildly between these countries), there is no denying there is a large number of people who can afford — and do buy — luxury cars in all these countries.

If we’re looking just at the countries that suffer from the most severe amounts of pollution, the data changes dramatically. In the graph below, I’m looking only at cities that are registering at above the WHO’s recommended 25 µg/m³ in the “most polluted” data.

It comes as no surprise that pollution has a choke-hold on China’s economy, with a recent report suggesting that a staggering 6.5 percent of the country’s GDP is being spent on pollution-related costs.

India is also struggling tremendously; the country has the dubious honor of claiming 13 of the 20 slots in the top most-polluted cities in the world. Only today, a 20-minute documentary entitled Death By Breath was released, exploring just how bad the air quality is in cities like Delhi, Patna and Gwalior.

What’s interesting about both of these markets is that they may just be perfect target markets for the sort of thing Tesla is trying to accomplish.

I believe that thinking “Hey, the HEPA filters make Tesla great for polluted places” is the wrong way of looking at it: It’s the other way around. Tesla was looking at the markets where it wants to make a huge splash, and added the advanced filtration precisely because these markets are struggling with severe pollution problems.

Tesla is going to sell so many cars

As I mentioned, HEPA filters in cars are nothing new, but the marketing around them has usually been subtle and understated, not to mention slightly negated by the fact that that giant, gas-chugging SUV you are driving may well have the cleanest passenger compartment in the world, but you’re still driving around and being part of the problem. By being a purely electric car company, Tesla is able to take the high road and offer something unique to an emerging class of wealthy individuals: People who care both about the air they breathe and about not being part of the problem.

In the world of luxury cars, Tesla is priced relatively averagely: There are a lot of different cars to choose from in this segment, and having a strong differentiating factor will make a tremendous different. Being an EV is only a small part of the appeal, doubly so in markets such as Beijing, Hong Kong, Delhi and Doha, where the Venn diagram of rampant pollution and concentrated wealth are at their peak.