Apologies... I was going over some old notes and saw this; realizing it's gone unanswered. Strange indeed that Newegg would list it. The seal does, in fact, do as you mentioned. Equally important is properly prepped and applied Hylomar. I must have cleaned the threaded ring threads on the inside of the FD a dozen times before I stopped getting old residual oil, grease and guck on my rag. Same thing with the outer threads of the threaded ring, though that was much easier to clean.