Amazon.com Inc. (AMZN), the electronic retailer, expects to get good returns both from selling the Kindle book device and from the content associated with it, the company's Chief Financial Officer said Wednesday.

"We think we can make good returns over time on both the device and the content," Thomas Szkutak told attendees at a technology conference hosted by Credit Suisse Wednesday.

He declined to provide specific figures, but Citigroup Global Markets has estimated that Amazon sold roughly 500,000 units of the Kindle last year and is on track for $1.2 billion in revenue related to the product by 2010, equivalent to 4% of its total sales.

The Kindle is facing challenges from a number of companies however. Sony Corp. (SNE), has sold more than 400,000 e-book readers since January 2009. Plastic Logic, a Mountain View, Calif.-based company, has also announced plans to launch a larger-screen based version of the reader. Apple Inc. (AAPL) is also reported to be considering launching a competitor.

-By Jessica Hodgson, Dow Jones Newswires; 415-439-6455; jessica.hodgson@dowjones.com