How to stop black streak on your caravan using Fenwicks

How to stop black streaks from appearing on your caravan using Fenwicks Black Streak Remover

[@kahlospirit24]

Is there anything that you should put on afterwards to help preserve the rubber?

[@lijimbu6338]

Try WD40 specialist high performance silicone lubricant or any of the good quality silicone lubricants. I hear talc powder is just as good as well.

[@stevenbreach2561]

Used it,still have very faint marks