Dyson has taken its first step into wearable technology, with an eye-catching pair of over-ear headphones that come with an air-purifying mouth visor.

Best known for vacuum cleaners, Dyson has diversified in recent years with products such as fans and a hairdryer.

The headphones - dubbed Dyson Zone - are designed to tackle the growing issue of air pollution.

One reviewer said they would definitely "turn heads in the street".

Britta O'Boyle, deputy editor at gadget publication Pocket-lint, wrote: "Their design is certainly eye catching."

The sound quality was "excellent", she told the BBC News, and the headphones had a "lovely construction".

But as she had been unable to test the product outdoors, she could not say how effectively it would purify air or "how silly you feel wearing it".

The headphones go on sale in the autumn.

"We don't expect them to be cheap," O'Boyle added.

Global problem
The noise-cancelling headphones come with a motor, fan and air filters in each ear cup.

Air is sucked through the filters, capturing allergens and pollutants such as nitrogen and sulphur dioxide and brake dust.

And this purified air is then channelled to the nose and mouth via the visor, which is magnetically attached to the bottom of the headphones.

It is 97% effective at getting clean air to the lungs, the company says.

Track breathing
There are four purification modes, depending on whether the wearer is walking down a street or sitting down.

The headphones use sensors to track breathing and exertion and then toggle between modes.

They also come with:

an app that lets users specify their location and determines when the filter needs replacing
a face covering comes that slots into the visor
The product has four hours' battery life in low-filtration mode, according to Pocket-lint, or 1.5 hours in high filtration.

'Fresh air'
Chief engineer Jake Dyson said: "Air pollution is a global problem - it affects us everywhere we go."

"The Dyson Zone purifies the air your breathe on the move.

"And unlike face masks, it delivers a plume of fresh air without touching your face, using high-performance filters and two miniaturised air pumps."

The non-contact aspect was a "must" for the designers, to avoid discomfort and irritation.

It was also a first foray into audio for Dyson engineers.

The Dyson Zone has been six years - and 500 prototypes - in the making

Originally, a snorkel-like mouthpiece was paired with a backpack holding the motor and inner workings.

The Verge called the finished product "bizarre", stressing it was not an early April Fool's joke.

"While mask wearing has been normalised considerably over the past two years, we'll have to see whether customers will be willing to embrace this extremely odd-looking product," it wrote.

Gadget publication Stuff.tv called it "the wildest gadget we've ever tried".

And tech website Cnet said it looked "like something you'd see in a dystopian sci-fi movie".