AT&T will officially launch its 12-city 5G network by commencing of a compatible mobile hotspot on December 21st. The carrier has also detailed its first service tariff on the new network.

The device, revealed earlier on, is the Netgear Nighthawk 5G Mobile Hotspot. It will run primarily on millimeter wave spectrum — shorter cell range, but wider capacity — branded by AT&T as “5G+.” As the device is a hotspot, it will run on a data-only plan as an addition to customers’ active phone lines.

Generally, the Nighthawk will cost $499 and 15GB of data per month will be available at $70 per month. Customers in a pilot market will be able to take advantage of an introductory offer to receive both device and service free for “at least 90 days.”

The network has also clarified its plans for its first two 5G smartphones, both from Samsung. The second device, likely the Galaxy Note 10, is said to run on millimeter wave as well as 5G spectrum below 6GHz. As it stands that sub-6GHz infrastructure won’t be available until the second half of next year, the first device, likely the Galaxy S10, will also be relegated to the 5G+ spectrum.

The first 5G markets are Atlanta; Charlotte; Dallas; Houston; Indianapolis; Jacksonville, Florida; Louisville; Oklahoma City; New Orleans; Raleigh; San Antonio and; Waco, Texas. AT&T expects to launch 5G in the cities of Las Vegas, Los Angeles, Nashville, Orlando, San Diego, San Francisco and San Jose in the first half of 2019.