Check it out: Shoppers are issued with patented mate-detector

A supermarket chain unveiled its latest weapon in the battle for customers yesterday. Sainsbury is appealing directly to shoppers' hearts by handing out "love beepers" so they can "check out their perfect partner" in the aisles.

A supermarket chain unveiled its latest weapon in the battle for customers yesterday. Sainsbury is appealing directly to shoppers' hearts by handing out "love beepers" so they can "check out their perfect partner" in the aisles.

Last night, it allowed customers to test the gadget at its Finchley Road store, in north London, where 60 per cent of its customers are single.

Unfortunately, while the device imported from Hong Kong is supposed to attract customers to each other, it could have the opposite effect. Maria Thomas, 26, a publishing editor of nearby Hampstead, said that she would test drive the beeper with a group of girlfriends, "just to see who the sad men are".

Her friend Elnor Allhusen, 26, a business analyst who also shops at the store, was equally sceptical about the beeper's ability to find true love. "I'd do it for a laugh, but certainly not on my own," she said. "I certainly wouldn't rate my chances of meeting my life partner through it."

The beeper, the size of a chunky keyring, comes in male and female models, blue and pink respectively. Customers can key in their interests from a range of options: eating out, drinking, going to the cinema, shopping and romance.

When two shoppers carrying the devices pass each other they beep at once. If they have programmed their beepers with the same interest they will beep and flash continuously, suggesting a perfect love match.

Mike Cripps, 22, who is single, was willing to give the beeper a go, but not as a "serious pulling device". The programming system was too crude in his view. "Just because someone likes going to restaurants doesn't mean they are not an idiot. You're looking at a rather one-dimensional conversation. There's quite a danger of lonely people thinking it will cure all their ills."

Those considering a test drive of the love beeper should bear in mind that it works on the same principle as a device called the Gaydar. This is an electronic pager introduced to Britain earlier this year, which is carried by homosexuals. The Gaydar was designed to vibrate when people of similar sexual orientation carrying the same device approaches. Unfortunately, it had great appeal for small animals living in parks and also an unnerving tendency to set off car alarms.

Unlike the Gaydar, which retails at £21, Sainsbury's love beeper is free to customers, who can collect one when they go into the shop and hand it back when they leave. The retailer has invested in 1,000 of the devices, but if they prove successful during next week's trial they may be introduced at more stores across the country.

Catherine Colebrook, 21, a maths graduate who is single, was one of the few to welcome the beeper: "Nobody in London speaks to each other. Anything which encourages a bit of good-humoured interaction when you are out and about has to be a good thing. I have heard that supermarkets have become the new singles hang-out, but whenever I'm shopping I'm more concerned with what I put in my trolley than who else is there."

Even so, she would happily carry a beeper. But then, eyes widening, a terrible thought occurred to her: "What if you were the only person carrying one? You'd feel like a desperate no-hoper."