Ah, I see what I am looking at now, I initially thought it was the metal protectors near the heal, but it is the 'sandpaper' looking material actually on the frame behind the clutch cover How much are they? Looks like something not necessarily needed, but could prevent a possible scrape from a boot buckle
the pics a bit deceiving it looks better in real life more like textured rubber,few mms thick get them on r@g website about £20 odds just heat up area with hairdrier and peel backing and carefully apply,i touched up a frame scrape then seen these they suit frame texture well imho.