During a livestream today, T-Mobile announced December 6, 2019 as the official launch date for its national 5G service, which will rely on low-frequency 600MHz radio signals and new 5G devices to bring higher-speed service to 200 million customers on day one. Thanks to the initiative, which has been in the buildout process for a year, the carrier expects to have a basic blanket of 5G coverage in 5,000 cities and towns by the end of 2019.

T-Mobile previously confirmed that accessing 5G on its national 600MHz network will require one of two new devices: Samsung’s Galaxy Note10+ 5G or a OnePlus 7T Pro McLaren,┬áboth specifically customized for the carrier’s network. Similar devices released by Samsung and OnePlus for other carriers — including Sprint, which T-Mobile is in the process of merging with — will apparently not be able to access 5G on T-Mobile’s 600MHz towers.

While each major U.S. carrier has announced plans for a national 5G network, their launches have all been heavily caveated for different reasons. Rival Verizon has launched short-distance millimeter wave 5G for consumers in a handful of cities, while AT&T has debuted millimeter wave “5G+” in smaller parts of over 20 cities, but solely for business users. T-Mobile has released one device with support for high-speed millimeter wave 5G in a small collection of major cities, but promised to cover the entire U.S. with a slower version of 5G quickly, adding more and faster 5G towers throughout 2020.

It’s presently unclear how T-Mobile and Sprint will handle the consumer side of merging their separate 5G initiatives. The two are currently selling 5G phones and hotspots that may not be able to access each others’ full 5G networks, though the carriers might use software updates or device trade-ins to satisfy early adopters after the merger.

The T-Mobile/Sprint merger has been officially approved by both the FCC and Justice Department but remains held up in a legal battle with numerous state attorneys general. To increase the chances of resolving the legal impasse, T-Mobile CEO John Legere today said the carrier will give 10 million households with children free home internet access, offer 10 years of free data service to first responders, and include cheap $15-$25 monthly plans with 2GB to 5GB of data to make service available to more customers. However, Legere says these incentives and the company’s 5G coverage plans depend on finalization of the merger.