If your Motorhome has a set of Fiamma brackets / rails pre-installed already then one of the kits below will fit it, depending on the vertical gap between the rails/brackets.
If You think of the N in the Model being No brackets, and then the C = Compact, M = Medium and N = Normal gap
40-50cm Vertical Gap = Pro CN
50-80cm Vertical Gap = Pro MN
80-150cm Vertical Gap = Pro N