High quality cast iron materials which guarantees appropriate weight, strength, and metallurgy.
It is important to change your brake drums over time to get optimal braking performance. Brake drums will become smaller and smaller from wear and tear. Brake drums are not repairable, you would have to replace them if they are worn out or if not working properly (in some cases you can have them turned).
It is recommended to change both brake drums and shoes when drums needs to be replaced. When should you change them? Here are some indications: