Heavy Plates : all our cores have pieced heavy plates giving greater support at tube to header joint. Bonding : all cores fully oven baked for stronger core matrix, higher transfer heat and long life. Other manufactures use tube to fin expansion method which fails rapidly. Fin : cooper is standard on all our radiator cores. Special brass fin for corrosion resistance will be available in the near future. Many various fin style & designed are available to suit all various application condition. Warranty : we are so confident of the Quality and superior of our standard Heavy Duty product that we provide a 1 year conditional warranty on core matrix and solder work. Tube : our standard Heavy Duty core is fitted with a heavy duty, brass weld tube giving our cores extra strength, life expectancy & less machine down time. The Light Duty lock seam tube is also available is requested. Many other manufactured use this lesser quality tube as standard.