SEOUL, South Korea (AP) — South Korean electronics giant Samsung Electronics Co. is starting domestic sales of televisions powered by its internally developed operating system.

Samsung said sales of Tizen-powered ultra-HD TVs began Thursday in South Korea. The new TVs come in four sizes from 55-inch diagonally to 88-inch. The smallest model costs 5.49 million won ($5,047).

The products were announced last month at a trade show in Las Vegas.

The move represents Samsung’s expansion of its internally developed operating system into living rooms and eventually into kitchens and other corners of the home.

Kim Hyun-seok, head of Samsung’s TV business, said all of Samsung’s Internet-connected TVs will be powered by Tizen this year, as well as refrigerators, washing machines and robotic vacuums cleaners.