eBay launched its instant buying service to supplement its normal auction listings Monday, hoping to lure more traditional e-commerce users to its service. First announced in January, eBay Express allows users to purchase from multiple sellers using a single shopping cart.

The site is completely separate from eBay's main auctions, and has the appearance of a more traditional e-commerce store. Nearly 10 million listings are included, culled from the auction site's "Buy it Now" listings. A U.S. version is currently in "preview mode," allowing sellers and buyers to test out the service.

eBay Express is fully functional, however, meaning buyers will be able to shop and buy through the site. The company plans an announcement to the entire eBay community in early May, followed by a major advertising campaign in August.

"eBay Express was developed specifically for those online buyers looking for a convenient shopping experience," eBay Express Senior Director Jamie Iannone said in a note to eBay sellers. While initially available in the U.S., the auction site plans to launch a German version next quarter.

In order to offer products on eBay Express, a seller must accept PayPal as a form of payment. Additionally, the seller must have a feedback rating of 100 or more, of which 98 percent are positive. If the seller meets these requirements, their "Buy it Now" listings are automatically placed on the eBay Express site.

"With eBay Express, you get access to a whole new market, with virtually no extra effort on your part," the company said in a statement.