The LOFAR Two Meter Sky Survey LoTSS DR2
(:bibcode:`2022A&A...659A...1S`) obtained radio data from 27% of the
northern sky between 120 and 168 MHz in the year 2014 through 2020. This
service publishes polarization spectra of extragalactic radio sources
(radio galaxies and blazars) and the rotation measures derived from them.
We also give redshifts for all sources. The data has a spatial resolution
of 20 arcsec.
