Since a polyurea or poly-hybrid can be applied to almost anything, it’s easier to say what’s less advised (where it should not be applied). Those surfaces are chrome, galvanized metal, anti-stick plastics, or over any severe flaking corrosion or rust. For bare metal surfaces, scuffing plus suitable primer are recommended for best adhesion, and highly advised on some such as aluminum.
SL&C brand polyureas, poly hybrids, and epoxies may be applied to most other surface types with minimal surface preparation (generally just light scuffing). Always contact us first with any questions so we can properly advise to how to ensure the best results.