There are post boxes for household and industrial use. They also differ according to the way we install them such as mounted in the wall or even fixed on a post. These post boxes are built in a variety of materials such as aluminum, plastic or even steel. Whatever type you choose, what they all have in common is a locking system. This is necessary to ensure that a person or company mails are protected from either the elements of the weather and even from people and animals. There are some that are very large and are configured in such a way to hold large quantities of mail and packets. These types of boxes are usually made from stainless steal material and are finished with a coating of durable powder. They include a secure locking technique and the locks are usually made of zinc plated in order to minimize rusting. This does not only guarantee a lifetime of non maintenance service but also allows the post box to be painted in a number of different colors.