Pseudo-equivalent widths and velocities of the red-wing feature (attributed to Si IIλ6355) and Fe II lines in the spectra of SNe Ib compared with SNe Ic and Ic-BL. Different subtypes are color-coded, including the peculiar objects SN 2016coi and SN 2019ehk. The data points belonging to the same SN are connected by lines, and those measured from WiseRep spectra are shown with empty symbols. Each SN Ib is represented by a distinct symbol denoted in the legend of (b).