THIS IS A BRAND NEW 55-56 CHEVY CAR ALUMINUM HEATER CORE. THIS IS ONLY CORRECT FOR CARS WITH A DELUXE HEATER. A DELUXE HEATER HAS MULTIPLE LEVERS ON THE DASH CONTROL UNIT, A STANDARD HEATER ONLY HAS ONE TWIST KNOB SWITCH. THIS CORE WILL REPLACE THE ORIGINAL CORE PERFECTLY. THE BENEFIT TO THIS ALUMINUM CORE IS THAT IT WILL HOLD SLIGHTLY HIGHER PRESSURE THEN THE OLD BRASS HEATER CORES, WHICH IS NEEDED IF YOU ARE RUNNING A HIGHER POUND RATING RADIATOR CAP. THE STOCK HEATER CONTROL VALVE WILL MOUNT UP TO THIS CORE JUST LIKE THE ORIGINAL. SKU #4770