Hamburg - To meet the demands of tourists who are invariably surprised by the caprices of summertime weather, German researchers have developed a "convertible" canvas shoe that morphs into a sandal with the flick of a zipper.

And if the weather suddenly changes again (which it always does during a summer vacation), you just zip the canvas top back onto the sandal soles - while meanwhile putting up the top on your convertible rental car.

Best of all, you don't have to pack beach sandals in your luggage. You are already wearing two-in-one shoes. Arriving at the beach, you just remove the canvas tops and slip them into your backpack and - presto - you are wearing comfy sandals.

The new shoe, called the Nat-2, is the brainchild of shoe designer Stephen Yeung, who says he got the idea when packing for a trip.

"Why not create a whole new kind of shoe which is fashionable, smart for travelling and that fits into everybody's limited urban space?" Yeung says he asked himself.

Meeting Matthias and Sebastian Thies from K&T Germany in Munich was the turning point to making this revolutionary idea a reality.

"We redefined the old classic sneaker by using an international patented 2in1 zipper function," says Yeung. Thus, the Nat-2 interchangeable duo-function shoe was born."

As patent holder, Yeung and his company Daywell is in charge of Nat-2-production and facilities, while K&T Germany is responsible for worldwide distribution and marketing.

"Imagine being dressed properly and comfy wherever and whenever," says Yeung. That was my goal. By taking off the top by a zipper a second stylish shoe becomes visible."

Nat-2 shoes are available at various exclusive dealers in Britain and Europe and also via the Internet direct from nat-2. eu. (dpa)