Improper handling and hop, my old grid is broken after 3 years of loyal service (a bit light still as composed mainly of plastic). I decided to replace my rack and the knife in this article. I'm not disappointed shaving performance is significantly better. It is actually advise replacing grid and knives every 18 months, what is not necessarily done (notably for a cost issue). I do not remember my razor had been as effective. Good to know, the entire 51S (S for Silver Grey) is equivalent to 51B (Navy). Only the color of the plastic changes.
