Foreign orders supplied some of the Royal Navy's monitors. The Humber class had originally been intended for Brazil, while the Gorgon class had been intended for Norway. Some monitors received numerical designations instead of conventional names. HMS M33 survives as an example of that numbered group.
Notable Point · 3:41-4:35
Foreign orders and numbered names in the monitor force
The Humber and Gorgon classes began as foreign orders, while ships such as HMS M33 followed a numerical naming system.