The US carrier, AT&T, is launching its first mmWave network, 5G+, with the Galaxy S20+ and Galaxy S20 Ultra on March 6, 2020. At this time, the Galaxy S20+ and S20 Ultra are only smartphones compatible with the network.
Look at the 24K gold variant of the Galaxy S20, S20+, and S20 Ultra
According to AT&T, 5G+ will offer peak speeds of up to 2Gbps. Currently, the carrier offers 5G service in 80 markets, but 5G+ will only be available in “parts of 35 cities for customers with compatible plans and devices.”
AT&T is also launching 5G service in 22 new markets. The full list can be found here.