Fits 1992-1997 Chevrolet 350 LT1 Gen II Small Block. D-Shaped Ports, 1.40 Inch Ports;Manufactured from “Dead Soft” (solid) .043" thick copper material; .051" embossment around each exhaust port to seal irregular surfaces. Total gasket thickness .094"; Provides excellent sealing and durability; Conforms to and seals minor surface irregularities; For high performance street, drag race, oval track and turbocharged (extreme heat) applications;