Cast iron. This type of radiator has, unfortunately, more minuses than positive qualities. Firstly, cast iron products have a large weight. Secondly, they have poor heat transfer. It is also worth noting that cast -iron radiators require constant care, and, more precisely, paints. Most people are inclined to acquire cast-iron batteries due to the fact that they have a low cost. The advantages include durability, as well as resistance to corrosion.