Roku (ROKU) - Get Report shares were down almost 12% in Wednesday trading as Comcast (CMCSA) - Get Report announced it was releasing a new set-top box specifically designed for its broadband-only customers.

The new service, called XFinity Flex, delivers a number of convenient features for broadband streaming customers, including aggregating content from all of one's streaming services (including Netflix, Amazon and Hulu) all in one place; highlighting which programs are included in a customer's subscriptions to those services; and a digital dashboard that can show home security camera views, the weather and number of connected devices. 

Comcast's Xfinity Flex

Comcast will be giving the box free to its broadband only customers and thinks that the service will help reinforce its relationship with the growing number of customers that have cut the cable cord and only use streaming services.

"Video over internet is more a friend than foe -- we've said that many times," said Brian Roberts, Comcast's CEO, in announcing the new service at the Goldman Sachs Communacopia conference in New York City on Wednesday morning.

Comcast shares were up 0.5% to $46.90 in trading on Wednesday.

Roku shares were also hit hard on Sept. 10 after Apple (AAPL) - Get Report announced that its new streaming service, Apple TV+, would be priced significantly lower than expected at just $4.99 a month and that purchasers of any Apple hardware device would get one year free of the service.

Roku shares are still up 391% this year.

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