Position-velocity diagrams extracted from a slit of width 0.8″ along the NGC 424 CO (2-1) kinematic minor axis (top panel, PA = 28°, see Table 2) and major axis (bottom panel, PA = 118°). CO (2-1) emission is masked at S/N ≤ 3. White contours correspond to arbitrary levels of the observed emission. Black contours correspond to arbitrary levels extracted from the best-fit model cube obtained with MOKA^3D shown in Fig. C.3 and described in Sect. 4.1.