This is the oval block off plate on the front of the manifold. It includes the plate, gasket, two bolts and lock washers. This blocks off the port for the thermostat/switch that controlled the opening of the end carbs on vacuum linkage cars. I replace them in every restoration. The old plates rust away from the back side, often heavily pitted. Also, the gaskets get very brittle with age. Gasket is also sold separately.