Left: measured (filled dots) and predicted (red solid line) SED of the NGC 3447A/NGC 3447 system; blue, magenta, red, and azure dots indicate far-UV GALEX, from Marino et al. (2010), Swift-UVOT and SDSS (Tables 1 and 2), IRAS and AKARI-F (Catalog Archive Server, Yamauchi et al. 2011) data, respectively. Middle and right: comparison between the observed velocity profiles along the directions in Fig. 4, PA = 14.3° (middle) and PA = 65° (right), with those derived from the selected snapshot in the corresponding directions and within the same semi-angle sector (i.e. 25°). The velocity profiles are folded and rebinned within 5′′ (blue filled dots) to be compared with the same slices of the simulation (red solid and dotted lines), with the same binning.