It has become routine for customers to swipe their credit or debit cards at consoles in fast-food joints, gas stations and grocery stores.

So why do we still willingly hand over our plastic at sit-down restaurants?

Pay-at-the-table systems are popular in Europe and in other parts of the world, but they have not yet caught on in the United States -- largely because the equipment makers have not been able to point to a reason why restaurateurs should invest in the gear.

Manufacturers now see an opportunity.

A rise in the number of "skimming" scams in which servers use hand-held computers to quietly record customers' credit-card information and sell it is creating a sense of urgency.

So is an increased push by managers to speed the flow of diners during peak hours.

"Restaurants are the last holdout where you still give up your credit card. That's why we think this is the next logical step," said Paul Rasori, VeriFone's vice president of marketing.

VeriFone's most compact tableside system, the VX-670, is about the size of a thick remote control and sports a square LCD screen and a numerical keypad.

It accepts debit and credit cards and can automatically add tips.

Once the customer swipes a card, the information is sent wirelessly to a computer in the restaurant. A tiny printer spits out a receipt.

The Blade, a competitor from rival Hypercom, is a sleek, hand-held unit. But it also sports a touch screen that can double as a menu and an optional no-contact reader that lets customers wave their cards instead of swiping them.

Both companies are betting that restaurants will be more willing to buy the systems -- which can cost several hundred dollars -- as security threats increase.

Some studies suggest as much as 70 percent of all cases of credit-card skimming stem from restaurant scams.

A 2005 report by Fair Isaac, the fraud-detection specialist, detailed how handheld skimming devices could take seconds to transmit data wirelessly to a fraudster and advised merchants to use table-side devices so that cards are always in customers' hands. The pay-at-the-table manufacturers say there's another benefit: greater productivity.

"If we can tell them they can increase table turns on peak hours by 1 to 4 percent, what's that worth to businesses?" said Scott Goldthwaite, vice president of Hypercom's global business development.

But the market for the systems in North America -- estimated to be as large as $438 million -- has been slow to take off.

It's partly because manufacturers have not completely meshed their systems with cash registers and other hardware developed by restaurant management companies.

But it's also because many manufacturers have to sell the benefits more effectively, said George Peabody, director of emerging technologies advisory services at the Mercator Advisory Group.

"They've got to prove a real market need, and it's got to be really clear," Peabody said.

Neither VeriFone nor Hypercom would reveal the price of the units, but both have launched tests in U.S. markets to gauge how the American diner reacts.

Both companies specialize in secure electronic payment devices. Hypercom sells devices in Europe, China and Latin America. VeriFone sells in Europe, Israel and Southeast Asia.

At Ray's Killer Creek, an upscale steakhouse in the north Atlanta suburb of Alpharetta, the VeriFone system didn't take long to catch on.

Jim Wahlstrom, the restaurant's operating partner, spent roughly 10 minutes on briefing his servers about the technology.

"We're all used to grocery stores and ATM machines," he said. "We all operate with our credit cards and debit cards in our daily lives."

As customers filed into the restaurant on a recent weekday afternoon, many seemed unfazed by the new way to pay.

Wayne Smith and two friends had finished their steaks and were waiting for the $191 bill when his waiter plopped down the machine.

He scanned his card, touched the square denoting a 20 percent tip and waited for his receipt.

"I feel a little like I'm at Wal-Mart," Smith said.