Armour plating isn't just for aristocrats anymore as the world's seventh-largest economy grapples with high rates of kidnapping, murder and robbery.

DuPont (DD.N), widely known as a chemical maker, introduced its bulletproof Kevlar fibre and SentryGlas car kit Armura in 2008 to middle class Brazilian families with Chevrolets, Hondas and yes, even low-cost Kias.

Now, it wants to bulletproof taxis that will shuttle visitors between events for the 2014 World Cup soccer championship and 2016 Rio de Janeiro Olympic games.

"We wanted to bring a solution to a family that wants protection but doesn't have money to afford classic car armour," said Carlos Benatto, business manager for DuPont Armura.

Armura, sold only in Brazil, protects against bullets up to .38 calibre. Sales rose 70 percent in the first quarter of this year compared with 2011.

DuPont said annual sales of Armura amounted to tens of millions of U.S. dollars, but it declined to be more specific. Sales for the company's Safety & Protection unit, which makes Armura, rose 17 percent in 2011 to $3.9 billion.

The kit costs about $12,000 (21,984 reais), weighs roughly 200 pounds (90 kilograms), and takes 15 days to install. A DuPont-approved technician replaces a car's windows with SentryGlas, and puts Kevlar panels behind the door panels. Because it relatively light weight, the kit does not cut fuel efficiency, DuPont said.

Many middle-class families might struggle to afford Armura, which adds roughly 30 percent to the 59,900 reais cost of a Kia (000270.KS) Soul, but alternatives could prove to be more expensive.

DuPont said that more than 100 mechanics in Brazil offer car armouring services, cobbling together parts from different vendors that cost twice as much as Armura. Some of them might incorporate Kevlar.

Developed by DuPont in 1965, Kevlar is the industry standard for bulletproofing door panels, but it is also used in flak jackets, socks and tires. DuPont has even developed a Kevlar tornado and hurricane shelter.

DuPont's bet that customers would like the convenience of one kit designed to seamlessly integrate with their cars is also paying off not only because Armura can be installed in 11 vehicles, including Toyota's (7203.T) Corolla and the Chevrolet Cruze made by General Motors (GM.N).

DuPont said it is also talking to automakers about installing Armura in new vehicles.

Alexandre Sarafian, a 25-year-old sporting goods retailer in Sao Paulo, decided to bulletproof a Kia Sportage for his mother, even though he wanted to buy a different car, because the Sportage is compatible with Armura.

"This is to get away from the day-to-day violence ... which should be diminishing, but it's not," said Sarafian. "Bulletproofing can get expensive, and you don't really recover that cost when you sell the car. So it's better not to pay so much."

In Brazil, high rates of petty and violent crimes have fuelled the demand for security products and services. In Salvador, the country's third-largest city, the murder rate has more than doubled over the past year, in part because of a police strike.

Brazilians spend roughly $8 billion every year on private security, according to Brazil's biggest private guards' union. That's as much as the U.S. government spent on security contractors during the first four years of the Iraq war, data from the U.S. Congressional Budget Office showed.

Armura protects against most handguns commonly used in Brazil, Benatto said.

Sao Paulo's notorious traffic is partly a consequence of crime, as people too scared to take public transportation choose to drive. But thieves have discovered that traffic jams provide opportunities to prey upon the public.

"This is the type of thing we're trying to prevent," said Benatto.

Armura's success in Brazil has exceeded DuPont's expectations, so the company is planning to bring the kit to at least two other countries, but it would not name them.

(Reporting By Ernest Scheyder in New York; Additional reporting by Brad Haynes, Guillermo Parra-Bernal, Brian Winter, Bruno Marfinati and Alice Pereira in Sao Paulo)

• A Permanent Economic Emergency