These Ultra-Seal header gaskets fit 1969–1970 Ford Boss 302, 1971 Boss 351, and 1970–1974 351C-4V engines with rectangular ports measuring 1.90" x 2.20". Built with a high-temperature expanded steel core and graphite-faced sealing surface, they provide excellent heat resistance, strong torque retention, and long-lasting durability. The graphite layer conforms to minor imperfections and helps pull heat away from the cylinder head, while the steel core maintains sealing pressure to prevent gasket failure. Suitable for OE replacement or high-performance use, including street, drag race, and oval track applications. Can be trimmed for modified port shapes.

Features
• High-temperature steel core with graphite-faced sealing surface
• Strong torque retention prevents gasket failure
• Excellent heat resistance and thermal conductivity
• Conforms to minor port and flange irregularities
• Trimmable for modified ports
• Ideal for OE replacement and performance applications