Reffc
Established Member
As I already have loads of ACF50, I used that to treat a few odd rust spots starting to appear last autumn and they haven't shown back since. It doesn't just protect the surface, it also stops existing rust dead in it's tracks. The thin film left will get into the pores of the CI and provide longer term protection but once dry, after a wipe over with a clean rag I applied a coat of wax and intend to reapply regularly.