U.S. electronics retailer Best Buy Co plans to sell an iRex Technologies e-reader that links to the Barnes & Noble digital bookstore, the companies said on Wednesday.

The device from iRex, a spin-off of Royal Philips Electronics, will have an 8.1-inch touchscreen and will sell for $399 when it goes on sale at Best Buy later this month under the iRex DR800SG brand.

The gadget will compete in the hot market for digital book readers with rivals such as Kindle from Amazon.com Inc and e-readers from Sony Corp.

The iRex device will deliver e-books wirelessly via Verizon Wireless, owned by Verizon Communications and Vodafone Group Plc.

Brick-and-mortar booksellers such as retailer Barnes & Noble are looking to digital books to help them battle a slump in sales in the $25 billion U.S. book market as readers go on line or turn to visual entertainment.

In July Barnes & Noble unveiled its online bookstore, which will be the exclusive provider of digital books to another e-reader from Plastic Logic. That device will have a wireless connection to AT&T Inc network.

U.S. network operators have been looking to connect a wide array of consumer electronics and industrial devices to their networks in a bid to expand service revenues beyond cellphone connections as most people already have mobile phones.

Tony Lewis, the head of Verizon Wireless' open development program for certifying third-party device connections, said he is open to connecting rival e-readers as well as gadgets in different consumer categories, but declined to give details.

Verizon Wireless does not currently plans to sell the iRex in its stores, but Lewis said that the company's decision on whether or not to directly sell devices other than phones would depend on its agreement with specific vendors.

The opportunity always exists for distribution by Verizon, Lewis said.

In the last year, Verizon has certified 65 third party devices for connection to its network including a mini laptop and specialist devices, including a medical tablet computer and law enforcement equipment.

(Reporting by Sinead Carew in New York and Harro Ten Wolde in

Amsterdam; Editing by Tim Dobbyn)