Liquid Rubber DIY Etch Primer is a water-based rust-inhibiting primer for metal surfaces. It has been designed as a part of the Roof Restoration System to prime and protect raw metal surfaces and enhance the adhesion of our Thermal Coating. The correct application ensures maximum coverage of the surface coating. Etch Primer contains rust inhibitor and is suitable for bare metal surfaces with light-medium rust - that has been converted - if heavy rust is visible must use Waterproof Sealant prior to Etch Primer application. Features and Benefits: Promotes adhesion Excellent coverage High durability Water-based Easy application and clean up Suitable for: New or old steel Galvanized iron Alloys Non-ferrous metals