A British mother's chatroom safety device has helped win her the title of the world's top female inventor.
The device Mrs Ward created fits into a phone socket
Beautician Paula Ward was concerned about her 11-year-old daughter's safety during internet chats so she decided to invent a way to block unwanted numbers.
The Phone & Net Guard - which allows the user to bar specific numbers - could net the Surrey mother a fortune.
She became the first Briton to win the top title in the 20-year history of a competition staged in the US.
Mrs Ward beat 1,000 other hopefuls at Inpex, the world's largest invention trade show in Pittsburgh.
The Caterham mother thought of the idea two years ago when she began to worry about her daughter Stephanie's use of internet chat rooms.
"Stephanie came home from school one day and told me that she had been on a chat room and she was not very comfortable with the conversations online," said Mrs Ward.
"A week later I checked her computer and I saw a worrying conversation where she seemed to be arranging to meet someone at the park nearby."
After contacting BT, Mrs Ward was told her only option was a call barring system that blocked all outgoing calls except 999.
There was no system available that could bar selected phone numbers.
But rather than be put off, former model Mrs Ward set about learning the rudiments of telecom engineering and recruited a local electronics firm to build the prototype.
She tried approaching telecom giants Commtel UK, whose name she had seen on gadgets in shop windows.
Unable to secure an appointment by phone, she turned up at the company's offices in Corby, Northants, with the device and two of her
"I got the impression they thought they were dealing with an idiot," she
She proceeded to give them a demonstration of how the device worked.
"So I showed what it could do, and they all started clapping.
"They told me not to leave and got me to sign an
exclusive contract there and then. I was shocked, I just couldn't believe it."
The £29.95 device goes on sale for the first time at Homebase stores in August.
As well as preventing calls to specified numbers, it can also block broadband signals without affecting the normal phone line.
Mrs Ward won the UK Inventor of the Year title in 2003. She is now going on to develop other ideas, some of which first came to her several years ago.