NGC 661 is classified as an E+, with the UGC noting a diffuse
companion at 3.8 arcmin offset in PA 261 east of north.
Chamaraux et al. (1987) report a non-detection (<0.57 Jy-km s-1)
at the optical position and red-shift measured in one Arecibo
beam (3.9 arcmin FWHM), suggesting that our detection, with
it's 9.4 arcmin offset, may be due to either a companion of
NGC 661 or tidal debris.
Companion 3.8, 261, 0.6 x 0.5, very diffuse