Water heater
Made of aluminium
Aluminum radiators are one of the most common options for home heating. They are light in weight and can have the front closed or open. In addition, its corrosion resistance is superior to that of other materials. The reaction rate of this material is very high.
steel plate
They are also called sheet metal radiators, they are one of the most economical and for this reason perhaps one of the most commonly used alongside aluminum radiators. They can be made up of vertical members, or they can be a smooth but ribbed assembly. The response speed of these emitters is also very high.
source
Cast iron radiators are a slightly more expensive option in terms of material and assembly, which is why they are more likely to be discontinued. They are made of cast iron and can be seen in some spots that want to keep this type of material more retro in design. Its resistance and reaction speed are very high.