 For example, a standard 6 pin cylinder, which was designed to be operated by only one key, can be operated by up to 26 = 64 keys if there are two shear points in each chamber.Larger organizations, with more complex systems, may have several levels of master keys, where the top level key works in all of the locks in the system.To visualize this, it can be thought of as a hierarchical chart, or a tree.