Online auction company EBay Inc. said that it would add a "Skype Me" button to certain categories of listings, allowing prospective buyers to contact sellers directly through the Internet phone service it acquired last year for $2.6 billion.

EBay Chief Executive Meg Whitman said the function is one way the company was pressing its "Power of Three" strategy to make the most of its acquisitions of the PayPal online payment service in 2002 and Luxembourg-based Skype last year.

"Each of these businesses is incredibly powerful on its own," Whitman told about 15,000 eBay buyers, sellers, partners and employees at a convention in Las Vegas. "EBay is No. 1 in e-commerce, PayPal is No. 1 in online payments and Skype is No. 1 in voice communications."

"Together, however, we think these three businesses can make even greater things happen," she said.

In the free service, those who push the on-screen button will be able to contact sellers by voice, text chat or both to request more information about a specific item in real time, she said.

That will help eliminate so-called friction that can get in the way of a sale, especially in high price categories or those that require a lot of information before a deal is made, she said.

The San Jose, California-based company said users will have to download Skype software and buy headsets separately.

The button will be added in a trial starting June 19 on 14 categories of products where eBay determined instant communication can better facilitate trade, such as automotive GPS devices, NBA basketball cards, diamond solitaire rings, real estate, and cars and trucks, the company said.

EBay is also looking at combining the functions of PayPal and Skype, said spokesman Hani Durzy. One idea is allowing PayPal account holders to automatically send money to anyone on their Skype buddy list.