Left: line-of-sight velocity profile of the dense gas within each filament as a function of position form the well centres, i.e. position 8 for Fi-NW (purple dotted line), Fi-SE (red dashed-dotted line), Fi-NEs (blue dashed line), and position 31 for Fi-NEn (cyan solid line). Right: same as left panel but for the total (thermal+non-thermal) dense gas velocity dispersion.