The four stars are all double-lined spectroscopic binaries, none of which has been recognized as such previously, although they are all quite bright stars whose magnitudes range from 6-4 to 7-6. They are main-sequence systems apart from HD 212790, whose primary (at least) is a giant of about K2 type, and they have very unequal components except in the case of HD 64207. The primary components of HR 770 and HD 187160, and both components of the metal-weak system HD 64207, are F stars. HD 212790 has an orbital eccentricity close to 0-5; the other orbits are much less eccentric. The periods of HR 770 and HD 64207 are 269 and 152 days, respectively, while the other two systems have periods of nearly five years.
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