A WRIST band warning men when it is a woman’s time of the month has made it to the finals of a contest to find budding entrepreneurs.

Karl Dorn invented the wrist band designed to change colour when a woman is suffering the effects of her monthly menstrual cycle.

The invention has been selected as a finalist in the Who Wants To Be A Miller on Air competition, spearheaded by leading Southend businessman Philip Miller, who has put up a £100,000 prize for the winner.

The wrist band, called Help for Husbands, will live up to its name by monitoring the changes in a woman’s body temperature with an aim of helping men to be more understanding and sensitive towards their partners.

Serial inventor Karl, 42, competed against more than 160 entries from across Essex to be one of ten finalists in the competition.

Karl, a plasterer from Eastwood, is hoping the £100,000 prize-money will help develop the concept into a marketable product, which he hopes to retail for £5 with £1 being donated to charity.

The father-of-two, said: “It will be a visual aid so men can be more understanding. Women’s time of the month do not run like clock work, but if we know, then we can understand it more.

“The band is temperature sensitive because a woman’s body temperature fluctuates at certain times on the month.”

Another of Mr Dorn’s inventions proved successful in 2007 when he won £10,000 on Sky One’s the Big Idea for an energy-saving standby plug.

Mr Dorn continued: “The wristband will be sensitively packaged.

“It is a bit of a taboo subject and I was nervous about putting the idea forward, but it is to help couples to communicate more.”

Southend entrepreneur and businessman Philip Miller, along with a panel of business experts selected the business idea based on its originality and business potential.

Mr Miller said: “To get this huge amount of top quality entries just goes to prove Essex really does have the most entrepreneurial spirit in the UK. It has been an incredibly tough decision to pick just ten to take to the next stage and I am looking forward to giving them all a good grilling.”

The winner will be announced on March 11.