The affordable 1066x cards will offer maximum read and write rates of 160 MB/s and 120 MB/s, respectively, compared to 270 MB/s on Lexar's more expensive 1800x lineup.
https://www.notebookcheck.net/Lexar-launches-1066x-UHS-I-Silver-MicroSD-series-starting-at-29-USD.501012.0.html