✅ WHY CHOOSE POR-15 TOP COAT PAINT? – POR-15 is an industry standard for high performance protection against corrosion and rust. Our direct-to- metal coating is essential in all applications where there is a need to help preserve substrates susceptible to corrosion. POR-15 Top Coat provides excellent adhesion and best when used over POR-15 Rust Preventive Coating, works to provide a permanent barrier.