Rust Encapsulator? Anyone ever use this?

[LHMissions]

Eastwood Rust Converter - Convert Rust in One Step

[ClarkSJ]

I haven't used the Eastwood product, but Krylon and Rustoleum both make a spray rust converter that converts rust to a black material. You then need to paint the surface with any conventional paint. I have used these products on outside wrought iron, they both work well.