Cleaning rubber rings

[ajfotofilmagem]

Dear friend of the CR. Do you know any lens cleaner that leaves the rubber rings quite black, as new? ??? Obviously this product should be harmless for glass, adhesives, lubricants, etc.. : Thank you.

 

[Mt Spokane Photography]

I use a toothbrush with a weak soapy solution, lens cleaner works. If they have turned white from oxidation, they are exceedingly difficult to clean, since the outer layer must be rubbed away. In that case, spend $10 to replace it.
Get it from Canon, online resellers may just double the price