Custom machined 3 piece inlet flow guide kit that fits SBC GEN 1 heads. Size are Felpro 1204 inlet 1.23″ X 1.99″, 1205 inlet 1.265″ X2.09″, 1206 inlet 1.31″ X 2.21″ all have 1/2″ radius. Material is plastic 3/4″ thick black satin finish. Discard the clay and improve your repeatability in flow testing with a machined IFG. Please e-mail us if you have any questions.