Original NOS 529048 exhaust gaskets for 1957-1958 Pontiac 370 and GMC Truck Series 10-50 with 336 engines based off the 370. This would be an early style gasket for those 336 engines prior to engine serial number 35000. May fit other years. Please ensure proper fitment prior to purchase. Sale is for a single pair. Each is sold in it’s original GM wrapper.