I am (re)installing an FSA slk K-Force carbon crank on my roadie. On the non drive side there was a small washer/o-ring between the crank arm and BB bearing contact. The washer seemed to have been installed with some kind of silicon or other blue plastic material or it used to be a metal/synthetic o-ring before I wore it down riding. I looked online and it mentions the o-rings that get installed between the crank arm and BB but doesnt say whether they are plastic coated or metal with some kind of compound applied at install time. Does anyone know the deal here? Do I need to track down a new part or can I put the metal ring back on it as is?